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GAMESS  INTRO  INPUT  TESTS  REFS

                                        (28 Jul 99)
        Section 2 - Input Description

    This section of the manual describes the input to
GAMESS.  The section is written in a reference, rather
than tutorial fashion.  However, there are frequent
reminders that more information can be found on a
particular input group, or type of calculation, in the
'Further Information' section of this manual.  There are
also a number of examples shown in the 'Input Examples'
section.

    It is useful to note that this chapter of the manual
can be searched online by means of the "gmshelp" command,
if your computer is of the Unix type.  A command such as
"gmshelp scf" will display the $SCF input group.  With
no arguments, the gmshelp command will show you all input
group names.  Type "q" to exit the pager, and note that
some pagers will let you back up by means of "b".

    The order of this section is chosen to approximate the
order in which most people prepare their input ($CONTRL,
$BASIS/$DATA, $GUESS, and so on).  After that comes run
type related input, then properties input, input for two
different solvation models, integral related input, and
finally CI/MCSCF input.  The next page contains a list of
all possible input groups, in the order in which they can
be found in this section.
                                                         *
 name    function                          module:routine
 ----    --------                          --------------

Molecule, basis, wavefunction specification:

$CONTRL  chemical control data             INPUTA:START
$SYSTEM computer related control data     INPUTA:START
$BASIS  basis set                         INPUTB:BASISS
$DATA   molecule, basis set               INPUTB:MOLE
$ZMAT   coded z-matrix                    ZMATRX:ZMATIN
$LIBE   linear bend data                  ZMATRX:LIBE
$SCF    HF-SCF wavefunction control       SCFLIB:SCFIN
$SCFMI  SCF-MI input control data         SCFMI :MIINP
$MP2    2nd order Moller-Plesset          MP2   :MP2INP
$GUESS  initial orbital selection         GUESS :GUESMO
$VEC    orbitals              (formatted) GUESS :READMO

Potential energy surface options:

$STATPT geometry search control           STATPT:SETSIG
$TRUDGE nongradient optimization          TRUDGE:TRUINP
$TRURST restart data for TRUDGE           TRUDGE:TRUDGX
$FORCE  hessian, normal coordinates       HESS  :HESSX
$CPHF   coupled-Hartree-Fock options      CPHF  :CPINP
$HESS   force constant matrix (formatted) HESS  :FCMIN
$GRAD   gradient vector       (formatted) HESS  :EGIN
$DIPDR  dipole deriv. matrix  (formatted) HESS  :DDMIN
$VIB    HESSIAN restart data  (formatted) HESS  :HSSNUM
$MASS   isotope selection                 VIBANL:RAMS
$IRC    intirisic reaction path           RXNCRD:IRCX
$DRC    dynamic reaction path             DRC   :DRCDRV
$SURF   potential surface scan            SURF  :SRFINP

Interpretation, properties:

$LOCAL  orbital localization control      LOCAL :LMOINP
$TWOEI  J,K integrals         (formatted) LOCCD :TWEIIN
$ELMOM  electrostatic moments             PRPLIB:INPELM
$ELPOT  electrostatic potential           PRPLIB:INPELP
$ELDENS electron density                  PRPLIB:INPELD
$ELFLDG electric field/gradient           PRPLIB:INPELF
$POINTS property calculation points       PRPLIB:INPPGS
$GRID   property calculation mesh         PRPLIB:INPPGS
$PDC    MEP fitting mesh                  PRPLIB:INPPDC
$MOLGRF orbital plots                     PARLEY:PLTMEM
$STONE  distributed multipole analysis    PRPPOP:STNRD
$MOROKM Morokuma energy decomposition     MOROKM:MOROIN
$FFCALC finite field polarizabilities     FFIELD:FFLDX
$TDHF   time dependent HF NLO properties  TDHF  :TDHFX

Solvation models:

$EFRAG  effective fragment potentials     EFINP :EFINP
$FRAGNAMEspecific named fragment pot.     EFINP :RDSTFR
$FRGRPL inter-fragment repulsion          EFINP :RDDFRL
$PCM    polarizable continuum model       PCM   :PCMINP
$PCMCAV PCM cavity generation             PCM   :MAKCAV
$NEWCAV PCM escaped charge cavity         PCM   :DISREP
$DISBS  PCM dispersion basis set          PCMDIS:ENLBS
$DISREP PCM dispersion/repulsion          PCMVCH:MORETS
$SCRF   self consistent reaction field    SCRF  :ZRFINP

Integral and integral modification options:

$ECP    effective core potentials         ECPLIB:ECPPAR
$EFIELD external electric field           PRPLIB:INPEF
$INTGRL format for 2e- integrals          INT2A :INTIN
$TRANS  integral transformation           TRANS :TRFIN

MCSCF and CI wavefunctions, and their properties:

$CIINP  control of CI process             GAMESS:WFNCI
$DET    determinantal full CI for MCSCF   ALDECI:DETINP
$CIDET  determinantal full CI             ALDECI:DETINP
$DRT    distinct row table for MCSCF      GUGDRT:ORDORB
$CIDRT  distinct row table for CI         GUGDRT:ORDORB
$MCSCF  parameters for MCSCF              MCSCF :MCSCF
$MCQDPT multireference pert. theory       MCQDPT:MQREAD
$CISORT integral sorting                  GUGSRT:GUGSRT
$GUGEM  Hamiltonian matrix formation      GUGEM :GUGAEM
$GUGDIA Hamiltonian eigenvalues/vectors   GUGDGA:GUGADG
$GUGDM  1e- density matrix                GUGDM :GUGADM
$GUGDM2 2e- density matrix                GUGDM2:GUG2DM
$LAGRAN CI lagrangian matrix              LAGRAN:CILGRN
$TRFDM2 2e- density backtransformation    TRFDM2:TRF2DM
$TRANST transition moments, spin-orbit    TRNSTN:TRNSTX


* this column is more useful to programmers than to users.

==========================================================
$CONTRL group          (optional)

This is a free format group specifying global switches.

SCFTYP             together with MPLEVL or CITYP specifies
                   the wavefunction.  You may choose from

       = RHF       Restricted Hartree Fock calculation
                   (default)

       = UHF       Unrestricted Hartree Fock calculation

       = ROHF      Restricted open shell Hartree-Fock.
                   (high spin, see GVB for low spin)

       = GVB       Generalized valence bond wavefunction
                   or OCBSE type ROHF. (needs $SCF input)

       = MCSCF     Multiconfigurational SCF wavefunction
                   (this requires $DET or $DRT input)

       = NONE      indicates a single point computation,
                   rereading a converged SCF function.
                   This option requires that you select
                   CITYP=GUGA or ALDET, RUNTYP=ENERGY,
                   TRANSITN, or SPINORBT, and GUESS=MOREAD.

MPLEVL =           chooses Moller-Plesset perturbation
                   theory level, after the SCF.
                   See $MP2 and $MCQDPT input groups.
       = 0         skips the MP computation (default)
       = 2         performs a second order energy
                   correction.  MP2 is implemented only
                   for RHF, UHF, ROHF, and MCSCF wave
                   functions.  Gradients are available
                   only for RHF, so for the others you
                   may pick from RUNTYP=ENERGY, TRUDGE,
                   SURFACE, or FFIELD only.

CITYP  =           chooses CI computation after the SCF,
                   for any SCFTYP except UHF.
       = NONE      skips the CI. (default)
       = GUGA      runs the Unitary Group CI package,
                   which requires $CIDRT input.
                   Gradients are available only for RHF,
                   so for other SCFTYPs, you may choose
                   only RUNTYP=ENERGY, TRUDGE, SURFACE,
                   FFIELD, TRANSITN, or SPINORBT.
       = ALDET     runs the Ames Laboratory determinant
                   full CI package, requiring $CIDET
                   input.  RUNTYP=ENERGY only.

Obviously, at most one of MPLEVL or CITYP may be chosen.

RUNTYP             specifies the type of computation, for
                   example at a single geometry point:

       = ENERGY    Molecular energy. (default)
       = GRADIENT  Molecular energy plus gradient.
       = HESSIAN   Molecular energy plus gradient plus
                   second derivatives, including harmonic
                   harmonic vibrational analysis.  See the
                   $FORCE and $CPHF input groups.

                   multiple geometry options:

       = OPTIMIZE  Optimize the molecular geometry using
                   analytic energy gradients. See $STATPT.
       = TRUDGE    Non-gradient total energy minimization.
                   See groups $TRUDGE and $TRURST.
       = SADPOINT  Locate saddle point (transition state).
                   See the $STATPT group.
       = IRC       Follow intrinsic reaction coordinate.
                   See the $IRC group.
       = GRADEXTR  Trace gradient extremal.
                   See the $GRADEX group.
       = DRC       Follow dynamic reaction coordinate.
                   See the $DRC group.
       = SURFACE   Scan linear cross sections of the
                   potential energy surface.  See $SURF.

                   single geometry property options:

       = PROP      Properties will be calculated.  A $DATA
                   deck and converged $VEC group should be
                   input.  Optionally, orbital localization
                   can be done.  See $ELPOT, etc.
       = MOROKUMA  Performs monomer energy decomposition.
                   See the $MOROKM group.
       = TRANSITN  Compute radiative transition moment.
                   See the $TRANST group.
       = SPINORBT  Compute spin-orbit coupling.
                   See the $TRANST group.
       = FFIELD    applies finite electric fields, most
                   commonly to extract polarizabilities.
                   See the $FFCALC group.
       = TDHF      analytic computation of time dependent
                   polarizabilities.  See the $TDHF group.

    * * * * * * * * * * * * * * * * * * * * * * * * *
    Note that RUNTYPs involving the energy gradient,
    which are GRADIENT, HESSIAN, OPTIMIZE, SADPOINT,
    IRC, GRADEXTR, and DRC, cannot be used for any
    CI or MP2 computation, except when SCFTYP=RHF.
    * * * * * * * * * * * * * * * * * * * * * * * * *

EXETYP = RUN       Actually do the run. (default)
       = CHECK     Wavefunction and energy will not be
                   evaluated.  This lets you speedily
                   check input and memory requirements.
                   See the overview section for details.
       = DEBUG     Massive amounts of output are printed,
                   useful only if you hate trees.
       = routine   Maximum output is generated by the
                   routine named.  Check the source for
                   the routines this applies to.


MAXIT  =           Maximum number of SCF iteration cycles.
                   Pertains only to RHF, UHF, ROHF, or
                   GVB runs.  See also MAXIT in $MCSCF.
                   (default = 30)

                 * * * * * * *

ICHARG =           Molecular charge.  (default=0, neutral)

MULT   =           Multiplicity of the electronic state
       = 1         singlet (default)
       = 2,3,...   doublet, triplet, and so on.

   ICHARG and MULT are used directly for RHF, UHF, ROHF.
   For GVB, these are implicit in the $SCF input, while
   for MCSCF or CI, these are implicit in $DRT/$CIDRT or
   $DET/$CIDET input.  You must still give them correctly.

                 * * * * * * *

ECP    =           effective core potential control.
       = NONE      all electron calculation (default).
       = READ      read the potentials in $ECP group.
       = SBKJC     use Stevens, Basch, Krauss, Jasien,
                   Cundari potentials for all heavy
                   atoms (Li-Rn are available).
       = HW        use Hay, Wadt potentials for all the
                   heavy atoms (Na-Xe are available).

                 * * * * * * *

  * * * the next three control molecular geometry * * *

COORD  = choice for molecular geometry in $DATA.
       = UNIQUE    only the symmetry unique atoms will be
                   given, in Cartesian coords (default).
       = HINT      only the symmetry unique atoms will be
                   given, in Hilderbrandt style internals.
       = CART      Cartesian coordinates will be input.
                   Please read the warning just below!!!
       = ZMT       GAUSSIAN style internals will be input.
       = ZMTMPC    MOPAC style internals will be input.
       = FRAGONLY  means no part of the system is treated
                   by ab initio means, hence $DATA is not
                   given.  The system is specified by $EFRAG.

  Note that the CART, ZMT, ZMTMPC choices require input of
  all atoms in the molecule.  These three also orient the
  molecule, and then determine which atoms are unique.  The
  reorientation is very likely to change the order of the
  atoms from what you input.  When the point group contains
  a 3-fold or higher rotation axis, the degenerate moments
  of inertia often cause problems choosing correct symmetry
  unique axes, in which case you must use COORD=UNIQUE
  rather than Z-matrices.

  Warning:  The reorientation into principal axes is done
  only for atomic coordinates, and is not applied to the
  axis dependent data in the following groups: $VEC, $HESS,
  $GRAD, $DIPDR, $VIB, nor Cartesian coords of effective
  fragments in $EFRAG.  COORD=UNIQUE avoids reorientation,
  and thus is the safest way to read these.

  Note that the choices CART, ZMT, ZMTMPC require the use
  of a $BASIS group to define the basis set.  The first
  two choices might or might not use $BASIS, as you wish.

UNITS  = distance units, any angles must be in degrees.
       = ANGS      Angstroms (default)
       = BOHR      Bohr atomic units

NZVAR  = 0  Use Cartesian coordinates (default).
       = M  If COORD=ZMT or ZMTMPC and a $ZMAT is not given:
            the internal coordinates will be those defining
            the molecule in $DATA.  In this case, $DATA must
            not contain any dummy atoms.  M is usually 3N-6,
            or 3N-5 for linear.
       = M  For other COORD choices, or if $ZMAT is given:
            the internal coordinates will be those defined
            in $ZMAT.  This allows more sophisticated
            internal coordinate choices.  M is ordinarily
            3N-6 (3N-5), unless $ZMAT has linear bends.

  NZVAR refers mainly to the coordinates used by OPTIMIZE
  or SADPOINT runs, but may also print the internal's
  values for other run types.  You can use internals to
  define the molecule, but Cartesians during optimizations!

LOCAL  =          controls orbital localization.
       = NONE     Skip localization (default).
       = BOYS     Do Foster-Boys localization.
       = RUEDNBRG Do Edmiston-Ruedenberg localization.
       = POP      Do Pipek-Mezey population localization.
                  See the $LOCAL group.   Localization
                  does not work for SCFTYP=GVB or CITYP.

       * * * interfaces to other programs * * *

MOLPLT = flag that produces an input deck for a molecule
         drawing program distributed with GAMESS.
         (default is .FALSE.)

PLTORB = flag that produces an input deck for an orbital
         plotting program distributed with GAMESS.
         (default is .FALSE.)

AIMPAC = flag to create an input deck for Bader's atoms
         in molecules properties code. (default=.FALSE.)
         For information about this program, contact
             Richard F.W. Bader
             Dept. of Chemistry
             McMaster University
             Hamilton, Ontario  L8S-4M1 Canada
             bader@sscvax.cis.mcmaster.ca

RPAC   = flag to create the input files for Bouman and
         Hansen's RPAC electronic excitation and NMR
         shieldings program.  RPAC works only with
         RHF wavefunctions.  (inactive)

FRIEND = string to prepare input to other quantum
         programs, choose from
       = HONDO    for HONDO 8.2
       = MELDF    for MELDF
       = GAMESSUK for GAMESS (UK Daresbury version)
       = GAUSSIAN for Gaussian 9x
       = ALL      for all of the above

PLTORB, MOLPLT, and AIMPAC decks are written to file
PUNCH at the end of the job.  The two binary disk
files output by RPAC are written at the end of the
job.  Thus all of these correspond to the final
geometry encountered during the job.

In contrast, selecting FRIEND turns the job into a
CHECK run only, no matter how you set EXETYP.  Thus the
geometry is that encountered in $DATA.  The input is
added to the PUNCH file, and may require some (usually
minimal) massaging.

PLTORB and MOLPLT are written even for EXETYP=CHECK.
AIMPAC requires at least RUNTYP=PROP.  RPAC requires at
least RUNTYP=ENERGY, and you must take action to save
the binary files AOINTS and WORK15.

   The NBO program of Frank Weinhold's group can be
attached to GAMESS.  The input to control the natural
bond order analysis is read by the add in code, so is
not described here.  The NBO program is available by
anonymous FTP to ftp.osc.edu, in the directory
pub/chemistry/software/SOURCES/FORTRAN/nbo

       * * * computation control switches * * *

   For the most part, the default is the only sensible
value, and unless you are sure of what you are doing,
these probably should not be touched.

NPRINT =           Print/punch control flag
                   See also EXETYP for debug info.
                   (options -7 to 5 are primarily debug)
       = -7        Extra printing from Boys localization.
       = -6        debug for geometry searches
       = -5        minimal output
       = -4        print 2e-contribution to gradient.
       = -3        print 1e-contribution to gradient.
       = -2        normal printing, no punch file
       =  1        extra printing for basis,symmetry,ZMAT
       =  2        extra printing for MO guess routines
       =  3        print out property and 1e- integrals
       =  4        print out 2e- integrals
       =  5        print out SCF data for each cycle.
                   (Fock and density matrices, current MOs
       =  6        same as 7, but wider 132 columns output.
                   This option isn't perfect.
       =  7        normal printing and punching (default)
       =  8        more printout than 7. The extra output
                   is (AO) Mulliken and overlap population
                   analysis, eigenvalues, Lagrangians, ...
       =  9        everything in 8 plus Lowdin population
                   analysis, final density matrix.

NOSYM  = 0     the symmetry specified in $DATA is used
               as much as possible in integrals, SCF,
               gradients, etc.  (this is the default)
       = 1     the symmetry specified in the $DATA group
               is used to build the molecule, then
               symmetry is not used again.   Some GVB
               or MCSCF runs (those without a totally
               symmetric charge density) require you
               request no symmetry.

INTTYP = POPLE use fast Pople-Hehre routines for sp integral
               blocks, and HONDO Rys polynomial code for
               all other integrals.  (default)
       = HONDO use HONDO/Rys integrals for all integrals.
               This option produces slightly more accurate
               integrals but is also slower.

         When diffuse functions are used, the inaccuracy in
         Pople/Hehre sp integrals shows up as inaccurate
         LCAO coefficients in virtual orbitals.  This means
         the error in SCF (meaning RHF to MCSCF) energies is
         expected to be about 5d-8 Hartree, but the error in
         computations that OCCUPY the virtual orbitals may
         be much larger.  We have seen an energy error of
         1d-4 in an MP2 energy when diffuse functions were
         used.  We recommend that all MP2 or CI jobs with
         diffuse functions select INTTYP=HONDO.

NORMF  = 0     normalize the basis functions (default)
       = 1     no normalization

NORMP  = 0     input contraction coefficients refer to
               normalized Gaussian primitives. (default)
       = 1     the opposite.
                                                  $CONTRL

ITOL   =       primitive cutoff factor (default=20)
       = n     products of primitives whose exponential
               factor is less than 10**(-n) are skipped.

ICUT   = n     integrals less than 10.0**(-n) are not
               saved on disk. (default = 9)


            * * * restart options * * *

IREST  =       restart control options
               (for OPTIMIZE run restarts, see $STATPT)
               Note that this option is unreliable!
       = -1    reuse dictionary file from previous run,
               useful with GEOM=DAF and/or GUESS=MOSAVED.
               Otherwise, this option is the same as 0.
       = 0     normal run (default)
       = 1     2e restart (1-e integrals and MOs saved)
       = 2     SCF restart (1-,2-e integrls and MOs saved)
       = 3     1e gradient restart
       = 4     2e gradient restart

GEOM   =       select where to obtain molecular geometry
       = INPUT from $DATA input (default for IREST=0)
       = DAF   read from DICTNRY file (default otherwise)

    As noted in the first chapter, binary file restart is
not a well tested option!
==========================================================

$SYSTEM group         (optional)

    This group provides global control information for
your computer's operation.  This is system related input,
and will not seem particularly chemical to you!

TIMLIM =  time limit, in minutes.  Set to about 95 percent
          of the time limit given to the batch job so that
          GAMESS can stop itself gently.  (default=600.0)

MWORDS =  the maximum replicated memory which your job can
          use, on every node.  This is given in units of
          1,000,000 words (as oppsed to 1024*1024 words),
          where a word is always a 64 bit quantity.  Most
          systems allocate this memory at run time, but
          some more primitive systems may have an upper
          limit chosen at compile time.  (default=1)
          In case finer control over the memory is needed,
          this value can be given in units of words by
          using the keyword MEMORY instead of MWORDS.

KDIAG  =    diagonalization control switch
       = 0  use a vectorized diagonalization routine
            if one is available on your machine,
            else use EVVRSP. (default)
       = 1  use EVVRSP diagonalization.  This may
            be more accurate than KDIAG=0.
       = 2  use GIVEIS diagonalization
            (not as fast or reliable as EVVRSP)
       = 3  use JACOBI diagonalization
            (this is the slowest method)

COREFL =  a flag to indicate whether or not GAMESS
          should produce a "core" file for debugging
          when subroutine ABRT is called to kill
          a job.  This variable pertains only to
          UNIX operating systems.  (default=.FALSE.)


* * * the next three refer to parallel GAMESS * * *

The next three apply only to parallel runs, and as they
are more or less obsolete, their use is discourged.

BALTYP =  Parallel load balence scheme
          LOOP turns off dynamic load balancing (DLB)
          NXTVAL uses dynamic load balancing
          (default = LOOP)

XDR    =  a flag to indicate whether or not messages
          should be converted into a generic format
          known as external data representation.
          If true, messages can exchange between
          machines of different vendors, at the cost
          of performing the data type conversions.
          (default=.FALSE.)  --inactive at present--

PTIME  =  a logical flag to print extra timing info
          during parallel runs.  This is not currently
          implemented.

==========================================================

$BASIS group          (optional)

    This group allows certain standard basis sets to be
easily given.  If this group is omitted, the basis set
must be given instead in the $DATA group.

GBASIS =        Name of the Gaussian basis set.
       = MINI - Huzinaga's 3 gaussian minimal basis set.
                Available H-Rn.
       = MIDI - Huzinaga's 21 split valence basis set.
                Available H-Rn.
       = STO  - Pople's STO-NG minimal basis set.
                Available H-Xe, for NGAUSS=2,3,4,5,6.
       = N21  - Pople's N-21G split valence basis set.
                Available H-Xe, for NGAUSS=3.
                Available H-Ar, for NGAUSS=6.
       = N31  - Pople's N-31G split valence basis set.
                Available H-Ne,P-Cl for NGAUSS=4.
                Available H-He,C-F for NGAUSS=5.
                Available H-Ar, for NGAUSS=6.
                For Ga-Kr, N31 selects the BC basis.
       = N311 - Pople's "triple split" N-311G basis set.
                Available H-Ne, for NGAUSS=6.
                Selecting N311 implies MC for Na-Ar.
       = DZV  - "double zeta valence" basis set.
                a synonym for DH for H,Li,Be-Ne,Al-Cl.
                (14s,9p,3d)/[5s,3p,1d] for K-Ca.
                (14s,11p,5d/[6s,4p,1d] for Ga-Kr.
       = DH   - Dunning/Hay "double zeta" basis set.
                (3s)/[2s] for H.
                (9s,4p)/[3s,2p] for Li.
                (9s,5p)/[3s,2p] for Be-Ne.
                (11s,7p)/[6s,4p] for Al-Cl.
       = TZV  - "triple zeta valence" basis set.
                (5s)/[3s] for H.
                (10s,3p)/[4s,3p] for Li.
                (10s,6p)/[5s,3p] for Be-Ne.
                a synonym for MC for Na-Ar.
                (14s,9p)/[8s,4p] for K-Ca.
                (14s,11p,6d)/[10s,8p,3d] for Sc-Zn.
       = MC   - McLean/Chandler "triple split" basis.
                (12s,9p)/[6s,5p] for Na-Ar.
                Selecting MC implies 6-311G for H-Ne.

    additional values for GBASIS are on the next page.

     * * * the next two are ECP bases only * * *

GBASIS = SBKJC- Stevens/Basch/Krauss/Jasien/Cundari
                valence basis set, for Li-Rn.  This choice
                implies an unscaled -31G basis for H-He.
       = HW   - Hay/Wadt valence basis.
                This is a -21 split, available Na-Xe,
                except for the transition metals.
                This implies a 3-21G basis for H-Ne.

     * * * semiempirical basis sets * * *

         The elements for which these exist can be found
         in the 'further information' section of this
         manual.  If you pick one of these, all other data
         in this group is ignored.  Semi-empirical runs
         actually use valence-only STO bases, not GTOs.

GBASIS = MNDO - selects MNDO model hamiltonian

       = AM1  - selects AM1 model hamiltonian

       = PM3  - selects PM3 model hamiltonian


NGAUSS = the number of Gaussians (N).   This parameter
         pertains only to GBASIS=STO, N21, N31, or N311.

NDFUNC = number of heavy atom polarization functions to
         be used.  These are usually d functions, except
         for MINI/MIDI.  The term "heavy" means Na on up
         when GBASIS=STO, HW, or N21, and from Li on up
         otherwise.  The value may not exceed 3.  The
         variable POLAR selects the actual exponents to
         be used, see also SPLIT2 and SPLIT3. (default=0)

NFFUNC = number of heavy atom f type polarization
         functions to be used on Li-Cl.  This may only
         be input as 0 or 1.  (default=0)

NPFUNC = number of light atom, p type polarization
         functions to be used on H-He.  This may not
         exceed 3, see also POLAR.  (default=0)

DIFFSP = flag to add diffuse sp (L) shell to heavy atoms.
         Heavy means Li-F, Na-Cl, Ga-Br, In-I, Tl-At.
         The default is .FALSE.

DIFFS  = flag to add diffuse s shell to hydrogens.
         The default is .FALSE.

Warning: if you use diffuse functions, please read
INTTYP in the $CONTRL group for numerical concerns.

POLAR  = exponent of polarization functions
       = POPLE     (default for all other cases)
       = POPN311   (default for GBASIS=N311, MC)
       = DUNNING   (default for GBASIS=DH, DZV)
       = HUZINAGA  (default for GBASIS=MINI, MIDI)
       = HONDO7    (default for GBASIS=TZV)

SPLIT2 = an array of splitting factors used when NDFUNC
         or NPFUNC is 2.  Default=2.0,0.5

SPLIT3 = an array of splitting factors used when NDFUNC
         or NPFUNC is 3.  Default=4.00,1.00,0.25

==========================================================


The splitting factors are from the Pople school, and are
probably too far apart.  See for example the Binning and
Curtiss paper.  For example, the SPLIT2 value will usually
cause an INCREASE over the 1d energy at the HF level for
hydrocarbons.

The actual exponents used for polarization functions, as
well as for diffuse sp or s shells, are described in the
'Further References' section of this manual.  This section
also describes the sp part of the basis set chosen by
GBASIS fully, with all references cited.

Note that GAMESS always punches a full $DATA group.  Thus,
if $BASIS does not quite cover the basis you want, you can
obtain this full $DATA group from EXETYP=CHECK, and then
change polarization exponents, add Rydbergs, etc.

==========================================================

$DATA group          (required)

    This group describes the global molecular data such as
point group symmetry, nuclear coordinates, and possibly
the basis set.  It consists of a series of free format
card images.

----------------------------------------------------------

-1-   TITLE     a single descriptive title card.

----------------------------------------------------------

-2-   GROUP, NAXIS

GROUP is the Schoenflies symbol of the symmetry group,
you may choose from
    C1, CS, CI, CN, S2N, CNH, CNV, DN, DNH, DND,
    T, TH, TD, O, OH.

NAXIS is the order of the highest rotation axis, and
must be given when the name of the group contains an N.
For example, "Cnv 2" is C2v.  "S2n 3" means S6.

For linear molecules, choose either CNV or DNH, and enter
NAXIS as 4.  Enter atoms as DNH with NAXIS=2.  If the
electronic state of either is degenerate, check the note
about the effect of symmetry in the electronic state
in the SCF section of REFS.DOC.

----------------------------------------------------------

    In order to use GAMESS effectively, you must be able
to recognize the point group name for your molecule.  This
presupposes a knowledge of group theory at about the level
of Cotton's "Group Theory", Chapter 3.

    Armed with only the name of the group, GAMESS is able
to exploit the molecular symmetry throughout almost all of
the program, and thus save a great deal of computer time.
GAMESS does not require that you know very much else about
group theory, although a deeper knowledge (character
tables, irreducible representations, term symbols, and so
on) is useful when dealing with the more sophisticated
wavefunctions.

Cards -3- and -4- are quite complicated, and are rarely
given.  A *SINGLE* blank card may replace both cards -3-
and -4-, to select the 'master frame', which is defined on
the next page.   If you choose to enter a blank card, skip
to the bottom of the next page.

                       Note!
If the point group is C1 (no symmetry), skip over cards
-3- and -4- (which means no blank card).

----------------------------------------------------------

-3-  X1, Y1, Z1, X2, Y2, Z2

For C1 group, there is no card -3- or -4-.
For CI group, give one point, the center of inversion.
For CS group, any two points in the symmetry plane.
For axial groups, any two points on the principal axis.
For tetrahedral groups, any two points on a two-fold axis.
For octahedral groups, any two points on a four-fold axis.

----------------------------------------------------------

-4-  X3, Y3, Z3, DIRECT

third point, and a directional parameter.
For CS group, one point of the symmetry plane,
              noncollinear with points 1 and 2.
For CI group, there is no card -4-.

For other groups, a generator sigma-v plane (if any) is
the (x,z) plane of the local frame (CNV point groups).

A generator sigma-h plane (if any) is the (x,y) plane of
the local frame (CNH and dihedral groups).

A generator C2 axis (if any) is the x-axis of the local
frame (dihedral groups).

The perpendicular to the principal axis passing through
the third point defines a direction called D1.  If
DIRECT='PARALLEL', the x-axis of the local frame coincides
with the direction D1.  If DIRECT='NORMAL', the x-axis of
the local frame is the common perpendicular to D1 and the
principal axis, passing through the intersection point of
these two lines.  Thus D1 coincides in this case with the
negative y axis.

----------------------------------------------------------

    The 'master frame' is just a standard orientation for
the molecule.  By default, the 'master frame' assumes that
    1.   z is the principal rotation axis (if any),
    2.   x is a perpendicular two-fold axis (if any),
    3.  xz is the sigma-v plane (if any), and
    4.  xy is the sigma-h plane (if any).
Use the lowest number rule that applies to your molecule.

        Some examples of these rules:
Ammonia (C3v): the unique H lies in the XZ plane (R1,R3).
Ethane (D3d): the unique H lies in the YZ plane (R1,R2).
Methane (Td): the H lies in the XYZ direction (R2).  Since
         there is more than one 3-fold, R1 does not apply.
HP=O (Cs): the mirror plane is the XY plane (R4).

In general, it is a poor idea to try to reorient the
molecule.  Certain sections of the program, such as the
orbital symmetry assignment, do not know how to deal with
cases where the 'master frame' has been changed.

Linear molecules (C4v or D4h) must lie along the z axis,
so do not try to reorient linear molecules.

You can use EXETYP=CHECK to quickly find what atoms are
generated, and in what order.  This is typically necessary
in order to use the general $ZMAT coordinates.




                     * * * *



Depending on your choice for COORD in $CONTROL,

    if COORD=UNIQUE, follow card sequence U
    if COORD=HINT,   follow card sequence U
    if COORD=CART,   follow card sequence C
    if COORD=ZMT,    follow card sequence G
    if COORD=ZMTMPC, follow card sequence M

Card sequence U is the only one which allows you to define
a completely general basis here in $DATA.

Recall that UNIT in $CONTRL determines the distance units.


----------------------------------------------------------

-5U-   Atom input.  Only the symmetry unique atoms are
input, GAMESS will generate the symmetry equivalent atoms
according to the point group selected above.

   if COORD=UNIQUE   NAME, ZNUC, X, Y, Z
   ***************

NAME  = 10 character atomic name, used only for printout.
        Thus you can enter H or Hydrogen, or whatever.
ZNUC  = nuclear charge.  It is the nuclear charge which
        actually defines the atom's identity.
X,Y,Z = Cartesian coordinates.

   if COORD=HINT
   *************

   NAME,ZNUC,CONX,R,ALPHA,BETA,SIGN,POINT1,POINT2,POINT3

NAME = 10 character atomic name (used only for print out).
ZNUC = nuclear charge.
CONX = connection type, choose from
  'LC'   linear conn.               'CCPA' central conn.
  'PCC'  planar central conn.              with polar atom
  'NPCC' non-planar central conn.   'TCT'  terminal conn.
  'PTC'  planar terminal conn.             with torsion
R    = connection distance.
ALPHA= first connection angle
BETA = second connection angle
SIGN = connection sign, '+' or '-'
POINT1, POINT2, POINT3 =
     connection points, a serial number of a previously
     input atom, or one of 4 standard points: O,I,J,K
     (origin and unit points on axes of master frame).
     defaults:  POINT1='O', POINT2='I', POINT3='J'

ref- R.L. Hilderbrandt, J.Chem.Phys. 51, 1654 (1969).
You cannot understand HINT input without reading this.

Note that if ZNUC is negative, the internally stored
basis for ABS(ZNUC) is placed on this center, but the
calculation uses ZNUC=0 after this.  This is useful
for basis set superposition error (BSSE) calculations.
----------------------------------------------------------

* * * If you gave $BASIS, continue entering cards -5U-
      until all the unique atoms have been specified.
      When you are done, enter a " $END " card.
* * * If you did not, enter cards -6U-, -7U-, -8U-.

----------------------------------------------------------
-6U-  GBASIS, NGAUSS, (SCALF(i),i=1,4)

GBASIS has exactly the same meaning as in $BASIS.  You may
choose from MINI, MIDI, STO, N21, N31, N311, DZV, DH, BC,
TZV, MC, SBKJC, or HW.  In addition, you may choose S, P,
D, F, G, or L to enter an explicit basis set.  Here, L
means both an s and p shell with a shared exponent.

NGAUSS is the number of Gaussians (N) in the Pople style
basis, or user input general basis.  It has meaning only
for GBASIS=STO, N21, N31, or N311, and S,P,D,F,G, or L.

Up to four scale factors may be entered.  If omitted,
standard values are used.  They are not documented as
every GBASIS treats these differently.  Read the source
code if you need to know more.  They are seldom given.
----------------------------------------------------------

* * * If GBASIS is not S,P,D,F,G, or L, either add more
      shells by repeating card -6U-, or go on to -8U-.
* * * If GBASIS=S,P,D,F,G, or L, enter NGAUSS cards -7U-.

----------------------------------------------------------
-7U- IG, ZETA, C1, C2

      IG = a counter, IG takes values 1, 2, ..., NGAUSS.
    ZETA = Gaussian exponent of the IG'th primitive.
      C1 = Contraction coefficient for S,P,D,F,G shells,
           and for the s function of L shells.
      C2 = Contraction coefficient for the p in L shells.
----------------------------------------------------------

* * * For more shells on this atom, go back to card -6U-.
* * * If there are no more shells, go on to card -8U-.

----------------------------------------------------------
-8U-    A blank card ends the basis set for this atom.
----------------------------------------------------------

Continue entering atoms with -5U- through -8U- until all
are given, then terminate the group with a " $END " card.

       --- this is the end of card sequence U ---

COORD=CART input:

----------------------------------------------------------

-5C- Atom input.

Cartesian coordinates for all atoms must be entered.  They
may be arbitrarily rotated or translated, but must possess
the actual point group symmetry.  GAMESS will reorient the
molecule into the 'master frame', and determine which
atoms are the unique ones.  Thus, the final order of the
atoms may be different from what you enter here.

      NAME, ZNUC, X, Y, Z

NAME  = 10 character atomic name, used only for printout.
        Thus you can enter H or Hydrogen, or whatever.
ZNUC  = nuclear charge.  It is the nuclear charge which
        actually defines the atom's identity.
X,Y,Z = Cartesian coordinates.

----------------------------------------------------------

Continue entering atoms with card -5C- until all are
given, and then terminate the group with a " $END " card.

       --- this is the end of card sequence C ---

COORD=ZMT input:       (GAUSSIAN style internals)

----------------------------------------------------------

-5G-      ATOM

Only the name of the first atom is required.
See -8G- for a description of this information.
----------------------------------------------------------

-6G-      ATOM  i1 BLENGTH

Only a name and a bond distance is required for atom 2.
See -8G- for a description of this information.
----------------------------------------------------------

-7G-      ATOM  i1 BLENGTH  i2 ALPHA

Only a name, distance, and angle are required for atom 3.
See -8G- for a description of this information.
----------------------------------------------------------

-8G-      ATOM  i1 BLENGTH  i2 ALPHA  i3 BETA i4

ATOM    is the chemical symbol of this atom.  It can be
        followed by numbers, if desired, for example Si3.
        The chemical symbol implies the nuclear charge.
i1      defines the connectivity of the following bond.
BLENGTH is the bond length "this atom-atom i1".
i2      defines the connectivity of the following angle.
ALPHA   is the angle "this atom-atom i1-atom i2".
i3      defines the connectivity of the following angle.
BETA    is either the dihedral angle "this atom-atom i1-
        atom i2-atom i3", or perhaps a second bond
        angle "this atom-atom i1-atom i3".
i4      defines the nature of BETA,
        If BETA is a dihedral angle, i4=0 (default).
        If BETA is a second bond angle, i4=+/-1.
        (sign specifies one of two possible directions).
----------------------------------------------------------

 o  Repeat -8G- for atoms 4, 5, ...
 o  The use of ghost atoms is possible, by using X or BQ
    for the chemical symbol.  Ghost atoms preclude the
    option of an automatic generation of $ZMAT.
 o  The connectivity i1, i2, i3 may be given as integers,
    1, 2, 3, 4, 5,...  or as strings which match one of
    the ATOMs.  In this case, numbers must be added to the
    ATOM strings to ensure uniqueness!
 o  In -6G- to -8G-, symbolic strings may be given in
    place of numeric values for BLENGTH, ALPHA, and BETA.
    The same string may be repeated, which is handy in
    enforcing symmetry.  If the string is preceeded by a
    minus sign, the numeric value which will be used is
    the opposite, of course.  Any mixture of numeric data
    and symbols may be given.  If any strings were given
    in -6G- to -8G-, you must provide cards -9G- and
    -10G-, otherwise you may terminate the group now with
    a " $END " card.

----------------------------------------------------------

-9G-   A blank line terminates the Z-matrix section.

----------------------------------------------------------

-10G-   STRING VALUE

STRING is a symbolic string used in the Z-matrix.
VALUE  is the numeric value to substitute for that string.

----------------------------------------------------------

Continue entering -10G- until all STRINGs are defined.
Note that any blank card encountered while reading -10G-
will be ignored.  GAMESS regards all STRINGs as variables
(constraints are sometimes applied in $STATPT).  It is not
necessary to place constraints to preserve point group
symmetry, as GAMESS will never lower the symmetry from
that given at -2-.  When you have given all STRINGs a
VALUE, terminate the group with a " $END " card.

       --- this is the end of card sequence G ---


                      * * * *



    The documentation for sequence G above and sequence M
below presumes you are reasonably familiar with the input
to GAUSSIAN or MOPAC.  It is probably too terse to be
understood very well if you are unfamiliar with these.  A
good tutorial on both styles of Z-matrix input can be
found in Tim Clark's book "A Handbook of Computational
Chemistry", published by John Wiley & Sons, 1985.

    Both Z-matrix input styles must generate a molecule
which possesses the symmetry you requested at -2-.  If
not, your job will be terminated automatically.

COORD=ZMTMPC input:       (MOPAC style internals)

----------------------------------------------------------

-5M-     ATOM

Only the name of the first atom is required.
See -8M- for a description of this information.
----------------------------------------------------------

-6M-     ATOM BLENGTH

Only a name and a bond distance is required for atom 2.
See -8M- for a description of this information.
----------------------------------------------------------

-7M-     ATOM BLENGTH j1 ALPHA j2

Only a bond distance from atom 2, and an angle with repect
to atom 1 is required for atom 3.  If you prefer to hook
atom 3 to atom 1, you must give connectivity as in -8M-.
See -8M- for a description of this information.
----------------------------------------------------------

-8M-     ATOM BLENGTH j1 ALPHA j2 BETA j3 i1 i2 i3

ATOM, BLENGTH, ALPHA, BETA, i1, i2 and i3 are as described
at -8G-.  However, BLENGTH, ALPHA, and BETA must be given
as numerical values only.  In addition, BETA is always a
dihedral angle.   i1, i2, i3 must be integers only.

The j1, j2 and j3 integers, used in MOPAC to signal
optimization of parameters, must be supplied but are
ignored here.  You may give them as 0, for example.
----------------------------------------------------------

Continue entering atoms 3, 4, 5, ... with -8M- cards until
all are given, and then terminate the group by giving a
" $END " card.

       --- this is the end of card sequence M ---

==========================================================
               This is the end of $DATA!



If you have any doubt about what molecule and basis set
you are defining, or what order the atoms will be
generated in, simply execute an EXETYP=CHECK job to find
out!

==========================================================

$ZMAT group      (required if NZVAR is nonzero in $CONTRL)

    This group lets you define the internal coordinates in
which the gradient geometry search is carried out.  These
need not be the same as the internal coordinates used in
$DATA.  The coordinates may be simple Z-matrix types,
delocalized coordinates, or natural internal coordinates.

    You must input a total of M=3N-6 internal coordinates
(M=3N-5 for linear molecules).  NZVAR in $CONTRL can be
less than M IF AND ONLY IF you are using linear bends.  It
is also possible to input more than M coordinates if they
are used to form exactly M linear combinations for new
internals.  These may be symmetry coordinates or natural
internal coordinates.  If NZVAR > M, you must input IJS and
SIJ below to form M new coordinates.  See DECOMP in $FORCE
for the only circumstance in which you may enter a larger
NZVAR without giving SIJ and IJS.

   **** IZMAT defines simple internal coordinates ****

IZMAT is an array of integers defining each coordinate.
The general form for each internal coordinate is
      code number,I,J,K,L,M,N

IZMAT =1 followed by two atom numbers. (I-J bond length)
      =2 followed by three numbers. (I-J-K bond angle)
      =3 followed by four numbers. (dihedral angle)
         Torsion angle between planes I-J-K and J-K-L.
      =4 followed by four atom numbers. (atom-plane)
         Out-of-plane angle from bond I-J to plane J-K-L.
      =5 followed by three numbers. (I-J-K linear bend)
         Counts as 2 coordinates for the degenerate bend,
         normally J is the center atom.  See $LIBE.
      =6 followed by five atom numbers. (dihedral angle)
         Dihedral angle between planes I-J-K and K-L-M.
      =7 followed by six atom numbers. (ghost torsion)
         Let A be the midpoint between atoms I and J, and
         B be the midpoint between atoms M and N.  This
         coordinate is the dihedral angle A-K-L-B.  The
         atoms I,J and/or M,N may be the same atom number.
         (If I=J AND M=N, this is a conventional torsion).
         Examples: N2H4, or, with one common pair, H2POH.

Example - a nonlinear triatomic, atom 2 in the middle:
      $ZMAT IZMAT(1)=1,1,2,  2,1,2,3,  1,2,3  $END
This sets up two bonds and the angle between them.
The blanks between each coordinate definition are
not necessary, but improve readability mightily.

     **** the next define delocalized coordinates ****

DLC    is a flag to request delocalized coordinates.
       (default is .FALSE.)

AUTO   is a flag to generate all redundant coordinates,
       automatically.  The DLC space will consist of all
       non-redundant combinations of these which can be
       found.  The list of redundant coordinates will
       consist of bonds, angles, and torsions only.
       (default is .FALSE.)

NONVDW is an array of atom pairs which are to be joined
       by a bond, but might be skipped by the routine
       that automatically includes all distances shorter
       than the sum of van der Waals radii.  Any angles
       and torsions associated with the new bond(s) are
       also automatically included.

The format for IXZMAT, IRZMAT, IFZMAT is that of IZMAT:

IXZMAT is an extra array of simple internal coordinates
       which you want to have added to the list generated
       by AUTO.  Unlike NONVDW, IXZMAT will add only the
       coordinate(s) you specify.

IRZMAT is an array of simple internal coordinates which
       you would like to remove from the AUTO list of
       redundant coordinates.  It is sometimes necessary
       to remove a torsion if other torsions around a bond
       are being frozen, to obtain a nonsingular G matrix.

IFZMAT is an array of simple internal coordinates which
       you would like to freeze.  See also FVALUE below.
       Note that IFZMAT/FVALUE work only with DLC, see the
       IFREEZ option in $STATPT to freeze coordinates if
       you wish to freeze simple or natural coordinates.

FVALUE is an array of values to which the internal
       coordinates should be constrained.  It is not
       necessary to input $DATA such that the initial
       values match these desired final values, but it is
       helpful if the initial values are not too far away.

   **** SIJ,IJS define natural internal coordinates ****

SIJ is a transformation matrix of dimension NZVAR x M,
    used to transform the NZVAR internal coordinates in
    IZMAT into M new internal coordinates.  SIJ is a
    sparse matrix, so only the non-zero elements are
    given, by using the IJS array described below.
    The columns of SIJ will be normalized by GAMESS.
    (Default: SIJ = I, unit matrix)

IJS is an array of pairs of indices, giving the row and
    column index of the entries in SIJ.

example - if the above triatomic is water, using
     IJS(1) = 1,1, 3,1,   1,2, 3,2,   2,3
     SIJ(1) = 1.0, 1.0,   1.0,-1.0,   1.0

    gives the matrix S=  1.0   1.0   0.0
                         0.0   0.0   1.0
                         1.0  -1.0   0.0

which defines the symmetric stretch, asymmetric stretch,
and bend of water.

references for natural internal coordinates:
  P.Pulay, G.Fogarasi, F.Pang, J.E.Boggs
     J.Am.Chem.Soc. 101, 2550-2560(1979)
  G.Fogarasi, X.Zhou, P.W.Taylor, P.Pulay
     J.Am.Chem.Soc. 114, 8191-8201(1992)
reference for delocalized coordinates:
  J.Baker, A. Kessi, B.Delley
     J.Chem.Phys. 105, 192-212(1996)

==========================================================

$LIBE group  (required if linear bends are used in $ZMAT)

A degenerate linear bend occurs in two orthogonal planes,
which are specified with the help of a point A.  The first
bend occurs in a plane containing the atoms I,J,K and the
user input point A.  The second bend is in the plane
perpendicular to this, and containing I,J,K.  One such
point must be given for each pair of bends used.

APTS(1)= x1,y1,z1,x2,y2,z2,...  for linear bends 1,2,...

Note that each linear bend serves as two coordinates, so
that if you enter 2 linear bends (HCCH, for example), the
correct value of NZVAR is M-2, where M=3N-6 or 3N-5, as
appropriate.

==========================================================


$SCF group         relevant if SCFTYP = RHF, UHF, or ROHF,
                   required if SCFTYP = GVB)

    This group of parameters provides additional control
over the RHF, UHF, ROHF, or GVB SCF steps.  It must be
used for GVB open shell or perfect pairing wavefunctions.

DIRSCF = a flag to activate a direct SCF calculation,
         which is implemented for all the Hartree-Fock
         type wavefunctions:  RHF, ROHF, UHF, and GVB.
         This keyword also selects direct MP2 computation.
         The default of .FALSE. stores integrals on disk
         storage for a conventional SCF calculation.

FDIFF  = a flag to compute only the change in the Fock
         matrices since the previous iteration, rather
         than recomputing all two electron contributions.
         This saves much CPU time in the later iterations.
         This pertains only to direct SCF, and has a
         default of .TRUE.  This option is implemented
         only for the RHF, ROHF, UHF cases.

         Cases with many diffuse functions in the basis
         set sometimes oscillate at the end, rather than
         converging.  Turning this parameter off will
         normally give convergence.

---- The next flags affect convergence rates.

EXTRAP = controls Pople extrapolation of the Fock matrix.
DAMP   = controls Davidson damping of the Fock matrix.
SHIFT  = controls level shifting of the Fock matrix.
RSTRCT = controls restriction of orbital interchanges.
DIIS   = controls Pulay's DIIS interpolation.
SOSCF  = controls second order SCF orbital optimization.
         (default=.TRUE. for RHF, Abelian group ROHF, GVB)
         (default=.FALSE. for UHF, non-Abelian group ROHF)
DEM    = controls direct energy minimization, which is
         implemented only for RHF.

defaults for     EXTRAP  DAMP  SHIFT RSTRCT  DIIS  SOSCF
ab initio:         T      F      F      F      T    T/F
semiempirical:     T      F      F      F      F     F

     The above parameters are implemented for all SCF
wavefunction types, except that DIIS will work for GVB
only for those cases with NPAIR=0 or NPAIR=1.  If both
DIIS and SOSCF are chosen, SOSCF is stronger than DIIS,
and so DIIS will not be used.

     Once either DIIS or SOSCF are initiated, any other
accelerator in effect is put in abeyance.

---- These parameters fine tune the various convergers.

NCONV  = n  SCF density convergence criteria.
         Convergence is reached when the density change
         between two consecutive SCF cycles is less than
         10.0**(-n) in absolute value.  One more cycle
         is executed after reaching convergence.   Less
         accuracy in NCONV gives questionable gradients.
         (default is n=5, except CI or MP2 gradients n=6)

SOGTOL = second order gradient tolerance.  SOSCF will be
         initiated when the orbital gradient falls below
         this threshold.  (default=0.25 au)

ETHRSH = energy error threshold for initiating DIIS.  The
         DIIS error is the largest element of e=FDS-SDF.
         Increasing ETHRSH forces DIIS on sooner.
         (default = 0.5 Hartree)

MAXDII = Maximum size of the DIIS linear equations, so
         that at most MAXDII-1 Fock matrices are used
         in the interpolation.  (default=10)

DEMCUT = Direct energy minimization will not be done
         once the density matrix change falls below
         this threshold.  (Default=0.5)

DMPCUT = Damping factor lower bound cutoff.  The damping
         damping factor will not be allowed to drop
         below this value. (default=0.0)
   note: The damping factor need not be zero to achieve
         valid convergence (see Hsu, Davidson, and
         Pitzer, J.Chem.Phys., 65, 609 (1976), see
         especially the section on convergence control),
         but it should not be astronomical either.

       * * * * * * * * * * * * * * * * * * * * *
       For more info on the convergence methods,
       see the 'Further Information' section.
       * * * * * * * * * * * * * * * * * * * * *

        ----- miscellaneous options -----

UHFNOS = flag controlling generation of the natural
         orbitals of a UHF function. (default=.FALSE.)

MVOQ   = 0  Skip MVO generation (default)
       = n  Form modified virtual orbitals, using a cation
            with n electrons removed.   Implemented for
            RHF, ROHF, and GVB.   If necessary to reach a
            closed shell cation, the program might remove
            n+1 electrons.  Typically, n will be about 6.

NPUNCH = SCF punch option
       =  0  do not punch out the final orbitals
       =  1  punch out the occupied orbitals
       =  2  punch out occupied and virtual orbitals
             The default is NPUNCH = 2.


        ----- options for virial scaling -----

VTSCAL =   A flag to request that the virial theorem be
           satisfied.  An analysis of the total energy
           as an exact sum of orbital kinetic energies
           is printed.  The default is .FALSE.

   This option is implemented for RHF, UHF, and ROHF,
   for RUNTYP=ENERGY, OPTIMIZE, or SADPOINT.  Related
   input is as follows:

SCALF  =   initial exponent scale factor when VTSCAL is
           in use, useful when restarting.  The default
           is 1.0.

MAXVT  =   maximum number of iterations (at a single
           geometry) to satisfy the energy virial theorem.
           The default is 20.

VTCONV =   convergence criterion for the VT, which is
           satisfied when 2 +  + R x dE/dR is less
           than VTCONV.  The default is 1.0D-6 Hartree.

For more information on this option, which is most
economically employed during a geometry search, see
M.Lehd and F.Jensen, J.Comput.Chem. 12, 1089-1096(1991).

    The next parameters define the GVB wavefunction.  Note
that ALPHA and BETA also have meaning for ROHF.  See also
MULT in the $CONTRL group.  The GVB wavefunction assumes
orbitals are in the order core, open, pairs.

NCO    =   The number of closed shell orbitals.  The
           default almost certainly should be changed!
           (default=0).

NSETO  =   The number of sets of open shells in the
           function.  Maximum of 10. (default=0)

NO     =   An array giving the degeneracy of each open
           shell set.  Give NSETO values.
           (default=0,0,0,...).

NPAIR  =   The number of geminal pairs in the -GVB-
           function.  Maximum of 12.  The default
           corresponds to open shell SCF (default=0).

CICOEF =   An array of ordered pairs of CI coefficients
           for the -GVB- pairs.  For example, a two pair
           case for water, say, might be
           CICOEF(1)=0.95,-0.05,0.95,-0.05.  If not
           normalized, as in the default, they will be.
           This parameter is useful in restarting a GVB
           run, with the current CI coefficients.
           (default = 0.90,-0.20,0.90,-0.20,...)

COUPLE =   A switch controlling the input of F, ALPHA,
           and BETA.  The default is to use internally
           stored values for these variables.   Note
           ALPHA and BETA can be given for -ROHF-, as
           well as -GVB-.  (Default=.FALSE.)

F      =   An vector of fractional occupations.

ALPHA  =   An array of A coupling coefficients given in
           lower triangular order.

BETA   =   An array of B coupling coefficients given in
           lower triangular order.

    Note:  The default for F, ALPHA, and BETA depends on
the state chosen.  Defaults for the most commonly occuring
cases are internally stored.

            * * * * * * * * * * * * * * * * * * *
            For more discussion of GVB/ROHF input
            see the 'further information' section
            * * * * * * * * * * * * * * * * * * *

==========================================================

$SCFMI group            (optional, relevant if SCFTYP=RHF)


    The SCF-MI method is a modification of the Roothaan
equations that avoids basis set superposition error (BSSE)
in intermolecular interaction calculations, by expanding
each monomer's orbitals using only its own basis set.
Thus, the resulting orbitals are not orthogonal.  The
presence of a $SCFMI group in the input triggers the use
of this option.

    The implementation is limited to two monomers, treated
at the RHF level.  The energy, gradient, and therefore
numerical hessian are available.  The SCF step may be run
in direct SCF mode.  The first 4 parameters must be given.
All atoms of monomer A must be given in $DATA before the
atoms of monomer B.

NA        = number of doubly occupied MOs on fragment A.
NB        = number of doubly occupied MOs on fragment B.
MA        = number of basis functions on fragment A.
MB        = number of basis functions on fragment B.

ITER      = maximum number of SCF-MI cycles, overriding
            the usual MAXIT value.  (default is 50).

DTOL      = SCF-MI density convergence criteria.
            (default is 1.0d-10)

ALPHA     = possible level shift parameter.
            (default is 0.0, meaning shifting is not used)

IOPT      =   prints additional debug information.
          = 0 standard outout (default)
          = 1 print for each SCF-MI cycle MOs, overlap
              between the MOs, CPU times.
          = 2 print some extra informations in secular
              systems solution.

MSHIFT    = debugging option that permits to shift all
            the memory pointer of the SCF-MI section
            of code of the quantity MSHIFT (default is 0).

==========================================================

   "Modification of Roothan Equations to Exclude BSSE
       from Molecular Interaction Calculations"
    E. Gianinetti, M. Raimondi, E. Tornaghi
    Int. J. Quantum Chem. 60, 157 (1996)

    A. Famulari, E. Gianinetti, M. Raimondi, and M. Sironi
    Int. J. Quantum Chem. (1997), submitted.

==========================================================

$MP2 group   (relevant to SCFTYP=RHF,UHF,ROHF if MPLEVL=2)

     Controls 2nd order Moller-Plesset perturbation runs,
if requested by MPLEVL in $CONTRL.  See also the DIRSCF
keyword in $SCF to select direct MP2.  MP2 is implemented
for RHF, high spin ROHF, or UHF wavefunctions.  Analytic
gradients and the first order correction to the wave-
function (i.e. properties) are available only for RHF.
The $MP2 group is usually not given.  See also $MCQDPT.

NCORE = n  Omits the first n occupied orbitals from the
           calculation.  The default for n is the number
           of chemical core orbitals.

MP2PRP=    a flag to turn on property computation for
           RHF MP2 jobs with RUNTYP=ENERGY.  This is
           appreciably more expensive than just evaluating
           the 2nd order energy correction alone, so the
           default is .FALSE.  Properties are always
           computed during gradient runs, when they are
           an almost free byproduct.

LMOMP2=    a flag to analyze the closed shell MP2 energy
           in terms of localized orbitals.  Any type of
           localized orbital may be used.  This option
           is implemented only for RHF, and its selection
           forces use of the METHOD=3 transformation.
           The default is .FALSE.

OSPT=      selects open shell spin-restricted perturbation.
           This parameter applies only when SCFTYP=ROHF.
           Please see the 'further information' section for
           more information about this choice.
    = ZAPT picks Z-averaged perturbation theory. (default)
    = RMP  picks RMP (aka ROHF-MBPT) perturbation theory.

CUTOFF=    transformed integral retention threshold, the
           default is 1.0d-9.

The last 3 input variables apply only to machines with
an incomplete DDI implementation, i.e. those computers
using ddi.src instead of a proper implementation.  At
present, only IBM SP & Cray T3E use the good parallel MP2.

NWORD =    controls memory usage.  The default uses all
           available memory.  (default=0)

METHOD= n  selects transformation method, 2 being the
           segmented transformation, and 3 being a more
           conventional two phase bin sort implementation.
           3 requires more disk, but less memory.  The
           default is to attempt method 2 first, and
           method 3 second.

AOINTS=    defines AO integral storage during conventional
           integral transformations, during parallel runs.
        DUP stores duplicated AO lists on each node, and
           is the default for parallel computers with slow
           interprocessor communication, e.g. ethernet.
        DIST distributes the AO integral file across all
           nodes, and is the default for parallel
           computers with high speed communications.

==========================================================

$GUESS group         (optional, relevant for all SCFTYP's)

    This group controls the selection of initial molecular
orbitals.

GUESS = Selects type of initial orbital guess.
      = HUCKEL   Carry out an extended Huckel calculation
                 using a Huzinaga MINI basis set, and
                 project this onto the current basis.
                 This is implemented for atoms up to Rn,
                 and will work for any all electron or
                 ECP basis set.  (default for most runs)
      = HCORE    Diagonalize the one electron Hamiltonian
                 to obtain the initial guess orbitals.
                 This method is applicable to any basis
                 set, but does not work as well as the
                 HUCKEL guess.
      = MOREAD   Read in formatted vectors punched by an
                 earlier run.  This requires a $VEC group,
                 and you MUST pay attention to NORB below.
      = MOSAVED  (default for restarts)  The initial
                 orbitals are read from the DICTNRY file
                 of the earlier run.
      = SKIP     Bypass initial orbital selection.  The
                 initial orbitals and density matrix are
                 assumed to be in the DICTNRY file.

    All GUESS types except 'SKIP' permit reordering of the
orbitals, carry out an orthonormalization of the orbitals,
and generate the correct initial density matrix.  The
initial density matrix cannot be generated for -CI- and
-MCSCF-, so property restarts for these wavefunctions will
require 'SKIP' which is an otherwise seldom used option.
Note that correct computation of a -GVB- density matrix
requires CICOEF in $SCF.  Another possible use for 'SKIP'
is to speed up a EXETYP=CHECK job, or a RUNTYP=HESSIAN job
where the hessian is supplied.


PRTMO = a flag to control printing of the initial guess.
        (default=.FALSE.)

NORB   = The number of orbitals to be read in the $VEC
         group.  This applies only to GUESS=MOREAD.

For -RHF-, -UHF-, -ROHF-, and -GVB-, NORB defaults to the
number of occupied orbitals.  NORB must be given for -CI-
and -MCSCF-.  For -UHF-, if NORB is not given, only the
occupied alpha and beta orbitals should be given, back to
back.  Otherwise, both alpha and beta orbitals must
consist of NORB vectors.
NORB may be larger than the number of occupied MOs, if you
wish to read in the virtual orbitals.  If NORB is less
than the number of atomic orbitals, the remaining orbitals
are generated as the orthogonal complement to those read.

NORDER = Orbital reordering switch.
       = 0  No reordering (default)
       = 1  Reorder according to IORDER and JORDER.

IORDER = Reordering instructions.
         Input to this array gives the new molecular
         orbital order.  For example, IORDER(3)=4,3 will
         interchange orbitals 3 and 4, while leaving the
         other MOs in the original order.  This parameter
         applies to all orbitals (alpha and beta) except
         for -UHF-, where it only affects the alpha MOs.
         (default is IORDER(i)=i )

JORDER = Reordering instructions.
         Same as IORDER, but for the beta MOs of -UHF-.

TOLZ   = level below which MO coefficients will be set
         to zero.  (default=1.0E-7)

TOLE   = level at which MO coefficients will be equated.
         This is a relative level, coefficients are set
         equal if one agrees in magnitude to TOLE times
         the other.  (default=5.0E-5)

SYMDEN = call a routine to project the totally symmetric
         component out of a density matrix.  This may be
         useful if the HUCKEL or HCORE give orbitals with
         inexact symmetry.  Since the density matrix is
         not idempotent, this can generate a non-variational
         energy on the first iteration.  For the same
         reason, this should never be used with orbitals
         of MOREAD quality.  (default=.FALSE.)

MIX    = rotate the alpha and beta HOMO and LUMO orbitals
         so as to generate inequivalent alpha and beta
         orbital spaces.  This pertains to UHF singlets
         only.  This may require use of NOSYM=1 in $CONTRL
         depending on your situation.  (default=.FALSE.)

==========================================================

$VEC group           (optional, relevant for all SCFTYP's)
                     (required if GUESS=MOREAD)

      This group consists of formatted vectors, as written
onto file PUNCH in a previous run.  It is considered good
form to retain the titling comment cards punched before
the $VEC card, as a reminder to yourself of the origin of
the orbitals.

      For Morokuma decompositions, the names of this group
are $VEC1, $VEC2, ... for each monomer, computed in the
identical orientation as the supermolecule.  For transition
moment or spin-orbit coupling runs, orbitals for states
one and possibly two are $VEC1 and $VEC2.

==========================================================

$STATPT group  (optional, for RUNTYP=OPTIMIZE or SADPOINT)

    This group controls the search for stationary points.
Note that NZVAR in $CONTRL determines if the geometry
search is conducted in Cartesian or internal coordinates.

METHOD = optimization algorithm selection.  Pick from

         NR   Straight Newton-Raphson iterate. This will
              attempt to locate the nearest stationary
              point, which may be of any order. There
              is no steplength control. RUNTYP can be
              either OPTIMIZE or SADPOINT

         RFO  Rational Function Optimization. This is
              one of the augmented Hessian techniques
              where the shift parameter(s) is(are) chosen
              by a rational function approximation to
              the PES. For SADPOINT searches it involves
              two shift parameters. If the calculated
              stepsize is larger than DXMAX the step is
              simply scaled down to size.

         QA   Quadratic Approximation. This is another
              version of an augmented Hessian technique
              where the shift parameter is chosen such
              that the steplength is equal to DXMAX.
              It is completely equivalent to the TRIM
              method. (default)

         SCHLEGEL The quasi-NR optimizer by Schlegel.

         CONOPT, CONstrained OPTimization. An algorithm
              which can be used for locating TSs.
              The starting geometry MUST be a minimum!
              The algorithm tries to push the geometry
              uphill along a chosen Hessian mode (IFOLOW)
              by a series of optimizations on hyperspheres
              of increasingly larger radii.
              Note that there currently are no restart
              capabilitites for this method, not even
              manually.

OPTTOL = gradient convergence tolerance, in Hartree/Bohr.
         Convergence of a geometry search requires the
         largest component of the gradient to be less
         than OPTTOL, and the root mean square gradient
         less than 1/3 of OPTTOL.  (default=0.0001)

NSTEP  = maximum number of steps to take.  Restart data
         is punched if NSTEP is exceeded. (default=20)

      --- the next four control the step size ---

DXMAX  = initial trust radius of the step, in Bohr.
         For METHOD=RFO, QA, or SCHLEGEL, steps will
         be scaled down to this value, if necessary.
         (default=0.3 for OPTIMIZE and 0.2 for SADPOINT)
         For METHOD=NR, DXMAX is inoperative.
         For METHOD=CONOPT, DXMAX is the step along the
         previous two points to increment the hypersphere
         radius between constrained optimizations.
         (default=0.1)

    the next three apply only to METHOD=RFO or QA:

TRUPD  = a flag to allow the trust radius to change as
         the geometry search proceeds.  (default=.TRUE.)

TRMAX  = maximum permissible value of the trust radius.
         (default=0.5 for OPTIMIZE and 0.3 for SADPOINT)

TRMIN  = minimum permissible value of the trust radius.
         (default=0.05)

     --- the next three control mode following ---

IFOLOW = Mode selection switch, for RUNTYP=SADPOINT.
         For METHOD=RFO or QA, the mode along which the
         energy is maximized, other modes are minimized.
         Usually refered to as "eigenvector following".
         For METHOD=SCHLEGEL, the mode whose eigenvalue
         is (or will be made) negative.  All other
         curvatures will be made positive.
         For METHOD=CONOPT, the mode along which the
         geometry is initially perturbed from the minima.
         (default is 1)
         In Cartesian coordinates, this variable doesn't
         count the six translation and rotation degrees.
         Note that the "modes" aren't from mass-weighting.

STPT   = flag to indicate whether the initial geometry
         is considered a stationary point. If .true.
         the initial geometry will be perturbed by
         a step along the IFOLOW normal mode with
         stepsize STSTEP. (default=.false.)
         The positive direction is taken as the one where
         the largest component of the Hessian mode is
         positive. If there are more than one largest
         component (symmetry), the first is taken as
         positive.
         Note that STPT=.TRUE. has little meaning with
         HESS=GUESS as there will be many degenerate
         eigenvalues.

STSTEP = Stepsize for jumping off a stationary point.
         Using values of 0.05 or more may work better.
         (default=0.01)

IFREEZ = array of internal coordinates to freeze.
         For example, IFREEZ(1)=1,3 freezes the two bond
         lengths in the $ZMAT example, while optimizing
         the angle.  You cannot freeze Cartesian coords.


 --- The next two control the hessian matrix quality ---

HESS   = selects the initial hessian matrix.
       = GUESS chooses a positive definite diagonal
               hessian. (default for RUNTYP=OPTIMIZE)
       = READ  causes the hessian to be read from a $HESS
               group. (default for RUNTYP=SADPOINT)
       = RDAB  reads only the ab initio part of the
               hessian, and approximates the effective
               fragment blocks.
       = RDALL reads the full hessian, then converts
               any fragment blocks to 6x6 T+R shape.
               (this option is seldom used).
       = CALC  causes the hessian to be computed, see
               the $FORCE group.

IHREP  = the number of steps before the hessian is
         recomputed.  If given as 0, the hessian will
         be computed only at the initial geometry if
         you choose HESS=CALC, and never again.  If
         nonzero, the hessian is recalculated every
         IHREP steps, with the update formula used on
         other steps.  (default=0)


   --- the next two control the amount of output ---
    Let 0 mean the initial geometry, L mean the last
    geometry, and all mean every geometry.
    Let INTR mean the internuclear distance matrix.
    Let HESS mean the approximation to the hessian.
    Note that a directly calculated hessian matrix
    will always be punched, NPUN refers only to the
    updated hessians used by the quasi-Newton step.

NPRT   =  1  Print INTR at all, orbitals at all
          0  Print INTR at all, orbitals at 0+L (default)
         -1  Print INTR at all, orbitals never
         -2  Print INTR at 0+L, orbitals never

NPUN   =  3  Punch all orbitals and HESS at all
          2  Punch all orbitals at all
          1  same as 0, plus punch HESS at all
          0  Punch all orbitals at 0+L, otherwise only
             occupied orbitals (default)
         -1  Punch occ orbitals at 0+L only
         -2  Never punch orbitals

HSSEND = a flag to control automatic hessian evaluation
         at the end of a successful geometry search.
         (default=.FALSE.)

MOVIE  = a flag to create a series of structural data
         which can be show as a movie by the MacIntosh
         program Chem3D.  The data is written to the
         file IRCDATA.  (default=.FALSE.)

 ---- the following parameters are quite specialized ----

PURIFY = a flag to help eliminate the rotational and
         translational degrees of freedom from the
         initial hessian (and possibly initial gradient).
         This is much like the variable of the same name
         in $FORCE, and will be relevant only if internal
         coordinates are in use.  (default=.FALSE.)

PROJCT = a flag to eliminate translation and rotational
         degrees of freedom from Cartesian optimizations.
         The default is .TRUE. since this normally will
         reduce the number of steps, except that this
         variable is set false when POSITION=FIXED is
         used during EFP runs.

ITBMAT = number of micro-iterations used to compute the
         step in Cartesians which corresponds to the
         desired step in internals.  The default is 5.

UPHESS = SKIP     do not update Hessian (not recommended)
         BFGS     default for OPTIMIZE using RFO or QA
         POWELL   default for OPTIMIZE using NR or CONOPT
         POWELL   default for SADPOINT
         MSP      mixed Murtagh-Sargent/Powell update
         SCHLEGEL only choice for METHOD=SCHLEGEL

RESTAR = Enables restart of an optimization run.  This
         can only be used with IREST .ne. 0 in $CONTRL.
         Use of this variable is discouraged.

 ---- NNEG, RMIN, RMAX, RLIM apply only to SCHLEGEL ----

NNEG   = The number of negative eigenvalues the force
         constant matrix should have. If necessary the
         smallest eigenvalues will be reversed. The
         default is 0 for RUNTYP=OPTIMIZE, and 1 for
         RUNTYP=SADPOINT.

RMIN   = Minimum distance threshold. Points whose root
         mean square distance from the current point is
         less than RMIN are discarded. (default=0.0015)

RMAX   = Maximum distance threshold. Points whose root
         mean square distance from the current point is
         greater than RMAX are discarded. (default=0.1)

RLIM   = Linear dependence threshold. Vectors from the
         current point to the previous points must not
         be colinear.  (default=0.07)
==========================================================

       * * * * * * * * * * * * * * * * * * * * *
       See the 'further information' section for
       some help with OPTIMIZE and SADPOINT runs
       * * * * * * * * * * * * * * * * * * * * *

==========================================================

$TRUDGE group       (optional, required for RUNTYP=TRUDGE)

    This group defines the parameters for a non-gradient
optimization of exponents or the geometry.  The TRUDGE
package is a modified version of the same code from Michel
Dupuis' HONDO 7.0 system, origially written by H.F.King.
Presently the program allows for the optimization of 10
parameters.

    Exponent optimization works only for uncontracted
primitives, without enforcing any constraints.  Two
non-symmetry equivalent H atoms would have their p
function exponents optimized separately, and so would two
symmetry equivalent atoms!  A clear case of GIGO.

    Geometry optimization works only in HINT internal
coordinates (see $CONTRL and $DATA groups).  The total
energy of all types of SCF wavefunctions can be optimized,
although this would be extremely stupid as gradient
methods are far more efficient.  The main utility is for
open shell MP2 or CI geometry optimizations, which may
not be done in any other way with GAMESS.


OPTMIZ = a flag to select optimization of either geometry
         or exponents of primitive gaussian functions.
       = BASIS    for basis set optimization.
       = GEOMETRY for geometry optimization (default).
         This means minima search only, there is no saddle
         point capability.

NPAR   = number of parameters to be optimized.

IEX    = defines the parameters to be optimized.

         If OPTMIZ=BASIS, IEX declares the serial number
    of the Gaussian primitives for which the exponents
    will be optimized.

         If OPTMIZ=GEOMETRY, IEX define the pointers to
    the HINT internal coordinates which will be optimized.
    (Note that not all internal coordinates have to be
    optimized.) The pointers to the internal coordinates
    are defined as:  (the number of atom on the input
    list)*10 + (the number of internal coordinate for that
    atom).  For each atom, the HINT internal coordinates
    are numbered as 1, 2, and 3 for BOND, ALPHA, and BETA,
    respectively.

P  =  Defines the initial values of the parameters to be
      optimized.  You can use this to reset values given
      in $DATA.  If omitted, the $DATA values are used.
      If given here, geometric data must be in Angstroms
      and degrees.


A complete example is a TCSCF multireference 6-31G
geometry optimization for methylene,

 $CONTRL SCFTYP=GVB CITYP=GUGA RUNTYP=TRUDGE
         COORD=HINT $END
 $BASIS  GBASIS=N31 NGAUSS=6 $END
 $DATA
Methylene TCSCF+CISD geometry optimization
Cnv 2

C    6.     LC  0.00  0.0  0.00  -  O  K
H    1.    PCC  1.00  53.  0.00  +  O  K  I
 $END
 $SCF    NCO=3 NPAIR=1 $END
 $TRUDGE OPTMIZ=GEOMETRY  NPAR=2
         IEX(1)=21,22   P(1)=1.08 $END
 $CIDRT  GROUP=C2V SOCI=.TRUE. NFZC=1 NDOC=3 NVAL=1
         NEXT=-1 $END

using GVB-PP(1), or TCSCF orbitals in the CI.  The starting
bond length is reset to 1.09, while the initial angle will
be 106 (twice 53).  Result after 17 steps is R=1.1283056,
half-angle=51.83377, with a CI energy of -38.9407538472

    Note that you may optimize the geometry for an excited
CI state, just specify
          $GUGDIA   NSTATE=5  $END
          $GUGDM    IROOT=3   $END
to find the equilibrium geometry of the third state (of
five total states) of the symmetry implied by your $CIDRT.

==========================================================

$TRURST group       (optional, relevant for RUNTYP=TRUDGE)

      This  group  specifies restart parameters for TRUDGE
runs and accuracy thresholds.

KSTART indicates the conjugate gradient direction in which
the optimization will proceed. ( default = -1 )
     -1 .... indicates that this is a non-restart run.
      0 .... corresponds to a restart run.

FNOISE accuracy of function values.
Variation smaller than FNOISE are not considered to be
significant (Def. 0.0005)

TOLF accuracy required of the function (Def. 0.001)

TOLR accuracy required of conjugate directions (Def. 0.05)

    For geometry optimization, the values which give
better results (closer to the ones obtained with gradient
methods) are:  TOLF=0.0001, TOLR=0.001, FNOISE=0.00001

==========================================================

$FORCE group

(optional, relevant for RUNTYP=HESSIAN,OPTIMIZE,SADPOINT)

    This group controls the computation of the hessian
matrix (the energy second derivative tensor, also known
as the force constant matrix), and an optional harmonic
vibrational analysis.  This can be a very time consuming
calculation.  However, given the force constant matrix,
the vibrational analysis for an isotopically substituted
molecule is very cheap.  Related input is HESS= in
$STATPT, and the $MASS, $HESS, $GRAD, $DIPDR, $VIB groups.

METHOD = chooses the computational method.
       = ANALYTIC is implemented only for SCFTYPs RHF,
                  ROHF, and GVB (when NPAIR is 0 or 1).
                  This is the default for these cases.
       = NUMERIC  is the default for all other cases:
                  UHF, MCSCF, and all MP2 or CI runs.

RDHESS = a flag to read the hessian from a $HESS group,
         rather than computing it.  This variable pertains
         only to RUNTYP=HESSIAN.  See also HESS= in the
         $STATPT group.  (default is .FALSE.)

PURIFY = controls cleanup
         Given a $ZMAT, the hessian and dipole derivative
         tensor can be "purified" by transforming from
         Cartesians to internals and back to Cartesians.
         This effectively zeros the frequencies of the
         translation and rotation "modes", along with
         their IR intensities.  The purified quantities
         are punched out.  Purification does change the
         Hessian slightly, frequencies at a stationary
         point can change by a wave number or so.  The
         change is bigger at non-stationary points.
         (default=.FALSE. if $ZMAT is given)

PRTIFC = prints the internal coordinate force constants.
         You MUST have defined a $ZMAT group to use this.
         (Default=.FALSE.)

  --- the next four apply only to METHOD=NUMERIC ----

NVIB   =    Number of displacements in each Cartesian
            direction for force field computation.
       = 1  Move one VIBSIZ unit in each positive
            Cartesian direction.  This requires 3N+1
            evaluations of the wavefunction, energy, and
            gradient, where N is the number of SYMMETRY
            UNIQUE atoms given in $DATA.  (default)
       = 2  Move one VIBSIZ unit in the positive direction
            and one VIBSIZ unit in the negative direction.
            This requires 6N+1 evaluations of the
            wavefunction and gradient, and gives a small
            improvement in accuracy.  In particular, the
            frequencies will change from NVIB=1 results by
            no more than 10-100 wavenumbers, and usually
            much less.  However, the normal modes will be
            more nearly symmetry adapted, and the residual
            rotational and translational "frequencies"
            will be much closer to zero.

VIBSIZ =    Displacement size (in Bohrs). Default=0.01

       Let 0 mean the Vib0 geometry, and
       D mean all the displaced geometries

NPRT   = 1  Print orbitals at 0 and D
       = 0  Print orbitals at 0 only (default)

NPUN   = 2  Punch all orbitals at 0 and D
       = 1  Punch all orbitals at 0 and occupied orbs at D
       = 0  Punch all orbitals at 0 only (default)



  ----- the rest control normal coordinate analysis ----

VIBANL = flag to activate vibrational analysis.
         (the default is .TRUE. for RUNTYP=HESSIAN, and
         otherwise is .FALSE.)

SCLFAC = scale factor for vibrational frequencies, used
         in calculating the zero point vibrational energy.
         Some workers correct for the usual overestimate
         in SCF frequencies by a factor 0.89.  ZPE or other
         methods might employ other factors, see A.P.Scott,
         L.Radom  J.Phys.Chem.  100, 16502-16513 (1996).
         The output always prints unscaled frequencies, so
         this value is used only during the thermochemical
         analysis.  (Default is 1.0)

TEMP   = an array of up to ten temperatures at which the
         thermochemistry should be printed out.  The
         default is a single temperature, 298.15 K.  To
         use absolute zero, input 0.001 degrees.

FREQ   = an array of vibrational frequencies.  If the
         frequencies are given here, the hessian matrix
         is not computed or read.  You enter any imaginary
         frequencies as negative numbers, omit the
         zero frequencies corresponding to translation
         and rotation, and enter all true vibrational
         frequencies.  Thermodynamic properties will be
         printed, nothing else is done by the run.

PRTSCN = flag to print contribution of each vibrational
         mode to the entropy.  (Default is .FALSE.)

DECOMP = activates internal coordinate analysis.
         Vibrational frequencies will be decomposed into
         "intrinsic frequencies", by the method of
         J.A.Boatz and M.S.Gordon, J.Phys.Chem., 93,
         1819-1826(1989).  If set .TRUE., the $ZMAT group
         may define more than 3N-6 (3N-5) coordinates.
         (default=.FALSE.)

PROJCT = controls the projection of the hessian matrix.
         The projection technique is described by
         W.H.Miller, N.C.Handy, J.E.Adams in J. Chem.
         Phys. 1980, 72, 99-112.  At stationary points,
         the projection simply eliminates rotational and
         translational contaminants.  At points with
         non-zero gradients, the projection also ensures
         that one of the vibrational modes will point
         along the gradient, so that there are a total of
         7 zero frequencies.  The other 3N-7 modes are
         constrained to be orthogonal to the gradient.
         Because the projection has such a large effect on
         the hessian, the hessian punched is the one
         BEFORE projection.  For the same reason, the
         default is .FALSE. to skip the projection, which
         is mainly of interest in dynamical calculations.

==========================================================

There is a set of programs for the calculation of kinetic
or equilibrium isotope effects from the group of Piotr
Paneth at the University of Lodz.  This ISOEFF package will
accept data computed by GAMESS, and can be downloaded at
      http://ck-sg.p.lodz.pl/isoeff/isoeff.html

==========================================================

$CPHF group         (relevant for analytic RUNTYP=HESSIAN)

    This group controls the solution of the response
equations, also known as coupled Hartree-Fock.

POLAR = a flag to request computation of the static
        polarizability, alpha.  Because this property
        needs 3 additional response vectors, beyond those
        needed for the hessian, the default is to skip the
        property.  (default = .FALSE.)

NWORD = controls memory usage for this step.  The default
        uses all available memory.  (default=0)

==========================================================

$HESS group (relevant for RUNTYP=HESSIAN if RDHESS=.TRUE.)
         (relevant for RUNTYP=IRC if FREQ,CMODE not given)
      (relevant for RUNTYP=OPTIMIZE,SADPOINT if HESS=READ)

    Formatted force constant matrix (FCM), i.e. hessian
matrix.  This data is punched out by a RUNTYP=HESSIAN job,
in the correct format for subsequent runs.  The first card
in the group must be a title card.

    A $HESS group is always punched in Cartesians.  It
will be transformed into internal coordinate space if a
geometry search uses internals.  It will be mass weighted
(according to $MASS) for IRC and frequency runs.

    The initial FCM is updated during the course of a
geometry optimization or saddle point search, and will be
punched if a run exhausts its time limit.  This allows
restarts where the job leaves off.  You may want to read
this FCM back into the program for your restart, or you
may prefer to regenerate a new initial hessian.  In any
case, this updated hessian is absolutely not suitable for
frequency prediction!

==========================================================

$GRAD group     (relevant for RUNTYP=OPTIMIZE or SADPOINT)
          (relevant for RUNTYP=HESSIAN when RDHESS=.TRUE.)

    Formatted gradient vector at the $DATA geometry.  This
data is read in the same format it was punched out.

    For RUNTYP=HESSIAN, this information is used to
determine if you are at a stationary point, and possibly
for projection.  If omitted, the program pretends the
gradient is zero, and otherwise proceeds normally.

    For geometry searches, this information (if known) can
be read into the program so that the first step can be
taken instantly.

==========================================================

$DIPDR group   (relevant for RUNTYP=HESSIAN if RDHESS=.T.)

Formatted dipole derivative tensor, punched in a previous
RUNTYP=HESSIAN job.  If this group is omitted, then a
vibrational analysis will be unable to predict the IR
intensities, but the run can otherwise proceed.

==========================================================

$VIB group   (relevant for RUNTYP=HESSIAN, METHOD=NUMERIC)

    Formatted card image -restart- data.  This data is
read in the format it was punched by a previous HESSIAN
job to the file IRCDATA.  Just add a " $END" card, and if
the final gradient was punched as zero, delete the last
set of data.  Normally, IREST in $CONTRL will NOT be used
in conjunction with a HESSIAN restart.  The mere presence
of this deck triggers the restart from cards.  This deck
can also be used to turn a single point differencing run
into double differencing, as well as recovering from time
limits, or other bombouts.

==========================================================

$MASS group     (relevant for RUNTYP=HESSIAN, IRC, or DRC)

    This group permits isotopic substitution during the
computation of mass weighted Cartesian coordinates.  Of
course, the masses affect the frequencies and normal modes
of vibration.

AMASS = An array giving the atomic masses, in amu. The
        default is to use the mass of the most abundant
        isotope.  Masses through element 104 are stored.

example - $MASS AMASS(3)=2.0140 $END
will make the third atom in the molecule a deuterium.

==========================================================

$IRC group                       (relevant for RUNTYP=IRC)

    This group governs the location of the intrinsic
reaction coordinate, a steepest descent path in mass
weighted corrdinates, that connects the saddle point to
reactants and products.

----- there are five integration methods chosen by PACE.

PACE = GS2    selects the Gonzalez-Schlegel second order
              method.  This is the default method.
              Related input is:

  GCUT   cutoff for the norm of the mass-weighted gradient
         tangent (the default is chosen in the range from
         0.00005 to 0.00020, depending on the value for
         STRIDE chosen below.
  RCUT   cutoff for Cartesian RMS displacement vector.
         (the default is chosen in the range 0.0005 to
         0.0020 Bohr, depending on the value for STRIDE)
  ACUT   maximum angle from end points for linear
         interpolation (default=5 degrees)
  MXOPT  maximum number of contrained optimization steps
         for each IRC point (default=20)
  IHUPD  is the hessian update formula.  1 means Powell,
         2 means BFGS (default=2)
  GA     is a gradient from the previous IRC point, and is
         used when restarting.
  OPTTOL is a gradient cutoff used to determine if the IRC
         is approaching a minimum.  It has the same meaning
         as the variable in $STATPT.  (default=0.0001)

PACE = LINEAR selects linear gradient following (Euler's
              method).  Related input is:

  STABLZ switches on Ishida/Morokuma/Komornicki reaction
         path stabilization.  The default is .TRUE.
  DELTA  initial step size along the unit bisector, if
         STABLZ is on.  Default=0.025 Bohr.
  ELBOW  is the collinearity threshold above which the
         stabilization is skipped.  If the mass weighted
         gradients at QB and QC are almost collinear, the
         reaction path is deemed to be curving very little,
         and stabilization isn't needed.  The default is
         175.0 degrees.  To always perform stabilization,
         input 180.0.
  READQB,EB,GBNORM,GB are energy and gradient data
         already known at the current IRC point.  If it
         happens that a run with STABLZ on decides to skip
         stabilization because of ELBOW, this data will be
         punched to speed the restart.

PACE = QUAD   selects quadratic gradient following.
              Related input is:

  SAB    distance to previous point on the IRC.
  GA     gradient vector at that historical point.


PACE = AMPC4  selects the fourth order Adams-Moulton
              variable step predictor-corrector.
              Related input is:

  GA0,GA1,GA2 which are gradients at previous points.


PACE = RK4    selects the 4th order Runge-Kutta variable
              step method.  There is no related input.



----- The next two are used by all PACE choices -----

STRIDE = Determines how far apart points on the reaction
         path will be.  STRIDE is used to calculate the
         step taken, according to the PACE you choose.
         The default is good for the GS2 method, which is
         very robust.  Other methods should request much
         smaller step sizes, such as 0.10 or even 0.05.
         (default = 0.30 sqrt(amu)-Bohr)
NPOINT = The number of IRC points to be located in this
         run. The default is to find only the next point.
         (default = 1)



----- The next two let you choose your output volume -----

    Let F mean the first IRC point found in this run,
    and L mean the final IRC point of this run.
    Let INTR mean the internuclear distance matrix.

NPRT   =  1  Print INTR at all, orbitals at all IRC points
          0  Print INTR at all, orbitals at F+L (default)
         -1  Print INTR at all, orbitals never
         -2  Print INTR at F+L, orbitals never

NPUN   =  1  Punch all orbitals at all IRC points
          0  Punch all orbitals at F+L, only occupied
             orbitals at IRC points between (default)
         -1  Punch all orbitals at F+L only
         -2  Never punch orbitals

----- The next two tally the reaction path results.  The
      defaults are appropriate for starting from a saddle
      point, restart values are automatically punched out.

NEXTPT = The number of the next point to be computed.
STOTAL = Total distance along the reaction path to next
         IRC point, in mass weighted Cartesian space.


----- The following controls jumping off the saddle point.
      If you give a $HESS group, FREQ and CMODE will be
      generated automatically.

SADDLE = A logical variable telling if the coordinates
         given in the $DATA deck are at a saddle point
         (.TRUE.) or some other point lying on the IRC
         (.FALSE.).  If SADDLE is true, either a $HESS
         group or else FREQ and CMODE must be given.
         (default = .FALSE.)  Related input is:

TSENGY = A logical variable controlling whether the energy
         and wavefunction are evaluated at the transition
         state coordinates given in $DATA.  Since you
         already know the energy from the transition state
         search and force field runs, the default is .F.
FORWRD = A logical variable controlling the direction to
         proceed away from a saddle point. The forward
         direction is defined as the direction in which
         the largest magnitude component of the imaginary
         normal mode is positive. (default =.TRUE.)
EVIB   = Desired decrease in energy when following the
         imaginary normal mode away from a saddle point.
         (default=0.0005 Hartree)
FREQ   = The magnitude of the imaginary frequency, given
         in cm**-1.
CMODE  = An array of the components of the normal mode
         whose frequency is imaginary, in Cartesian
         coordinates.  Be careful with the signs!

   You must give FREQ and CMODE if you don't give a $HESS
   group, when SADDLE=.TRUE.  The option of giving these
   two variables instead of a $HESS does not apply to the
   GS2 method, which must have a hessian input, even for
   restarts.  Note also that EVIB is ignored by GS2 runs.

==========================================================


            * * * * * * * * * * * * * * * * * *
            For hints about IRC tracking, see
            the 'further information' section.
            * * * * * * * * * * * * * * * * * *

==========================================================

$GRADEX group  (optional, for RUNTYP=GRADEXTR)

   This group controls the gradient extremal following
algorithm.  The GEs leave stationary points parallel to
each of the normal modes of the hessian.  Sometimes a GE
leaving a minimum will find a transition state, and thus
provides us with a way of finding that saddle point.  GEs
have many unusual mathematical properties, and you should
be aware that they normally differ a great deal from IRCs.

   The search will always be performed in cartesian
coordinates, but internal coordinates along the way may
be printed by the usual specification of NZVAR and $ZMAT.

METHOD = algorithm selection.
         SR   A predictor-corrector method due to Sun
              and Ruedenberg (default).
         JJH  A method due to Jorgensen, Jensen and
              Helgaker.

NSTEP  = maximum number of predictor steps to take.
         (default=50)

DPRED  = the stepsize for the predictor step.
         (default = 0.10)

STPT   = a flag to indicate whether the initial geometry
         is considered a stationary point. If .TRUE.,
         the geometry will be perturbed by STSTEP along
         the IFOLOW normal mode.
         (default = .TRUE.)

STSTEP = the stepsize for jumping away from a stationary
         point. (default = 0.01)

IFOLOW = Mode selection option.  (default is 1)
         If STPT=.TRUE., the intial geometry will be
         perturbed by STSTEP along the IFOLOW normal mode.
         Note that IFOLOW can be positive or negative,
         depending on the direction the normal mode
         should be followed in. The positive direction
         is defined as the one where the largest component
         of the Hessian eigenvector is positive.

         If STPT=.FALSE. the sign of IFOLOW determines
         which direction the GE is followed in. A positive
         value will follow the GE in the uphill direction.
         The value of IFOLOW should be set to the Hessian
         mode which is parallel to the gradient to avoid
         miscellaneous warning messages.

GOFRST = a flag to indicate whether the algorithm should
         attempt to locate a stationary point.  If .TRUE.,
         a straight NR search is performed once the NR
         step length drops below SNRMAX.  10 NR step are
         othen allowed, a value which cannot be changed.
         (default = .TRUE.)

SNRMAX = upper limit for switching to straight NR search
         for stationary point location.
         (default = 0.10 or DPRED, whichever is smallest)

OPTTOL = gradient convergence tolerance, in Hartree/Bohr.
         Used for optimizing to a stationary point.
         Convergence of a geometry search requires the
         rms gradient to be less than OPTTOL.
         (default=0.0001)

HESS   = selection of the initial hessian matrix, if
         STPT=.TRUE.
       = READ causes the hessian to be read from a $HESS
               group.
       = CALC causes the hessian to be computed. (default)

---- parameters on this page apply only to METHOD=SR ----

DELCOR = the corrector step should be smaller than this
         value before the next predictor step is taken.
         (default = 0.001)

MYSTEP = maximum number of micro iteration allowed to
         bring the corrector step length below DELCOR.
         (default=20)

SNUMH  = stepsize used in the numerical differentiation
         of the Hessian to produce third derivatives.
         (default = 0.0001)

HSDFDB = flag to select determination of third derivatives.
         At the current geometry we need the gradient, the
         Hessian, and the partial third derivative matrix
         in the gradient direction.

         If .TRUE., the gradient is calculated at the
         current geometry, and two Hessians are calculated
         at SNUMH distance to each side in the gradient
         direction.  The Hessian at the geometry is formed
         as the average of the two displaced Hessians.

         If .FALSE., both the gradient and Hessian are
         calculated at the current geometry, and one
         additional Hessian is calculated at SNUMH in the
         gradient direction.

         The default double-sided differentiation produces
         a more accurate third derivative matrix, at the
         cost of an additional wave function and gradient.
         (default = .TRUE.)

==========================================================

           * * * * * * * * * * * * * * * * * * *
           See the 'further information' section
           for some help with GRADEXTR runs.
           * * * * * * * * * * * * * * * * * * *

==========================================================

$DRC group                       (relevant for RUNTYP=DRC)

    This group governs the dynamical reaction coordinate,
a classical trajectory method based on quantum chemical
potential energy surfaces.  In GAMESS these may be either
ab initio or semi-empirical.  Because the vibrational
period of a normal mode with frequency 500 wavenumbers is
67 fs, a DRC needs to run for many steps in order to
sample a representative portion of phase space.  Almost
all DRCs break molecular symmetry, so build your molecule
with C1 symmetry in $DATA, or specify NOSYM=1 in $CONTRL.
Restart data can be found in the job's OUTPUT file, with
important results summarized to the IRCDATA file.

NSTEP  = The number of DRC points to be calculated, not
         including the initial point.  (default = 1000)

DELTAT = is the time step.  (default = 0.1 fs)

TOTIME = total duration of the DRC computed in a previous
         job, in fs.  The default is the correct value
         when initiating a DRC.  (default=0.0 fs)

                           * * *

      In general, a DRC can be initiated anywhere,
      so $DATA might contain coordinates of the
      equilibrium geometry, or a nearby transition
      state, or something else.  You must also
      supply an initial kinetic energy, and the
      direction of the initial velocity, for which
      there are a number of options:


EKIN   = The initial kinetic energy (default = 0.0 kcal/mol)
         See also ENM, NVEL, and VIBLVL regarding alternate
         ways to specify the initial value.

VEL    = an array of velocity components, in Bohr/fs.
         When NVEL is false, this is simply the direction
         of the velocity vector.  Its magnitude will be
         automatically adjusted to match the desired initial
         kinetic energy, and it will be projected so that
         the translation of the center of mass is removed.
         Give in the order vx1, vy1, vz1, vx2, vy2, ...

NVEL   = a flag to compute the initial kinetic energy from
         the input VEL using the sum of mass*VEL*VEL/2.
         This flag is usually selected only for restarts.
         (default=.FALSE.)

                           * * *

         The next two allow the kinetic energy to be
         partitioned over all normal modes.  The
         coordinates in $DATA are likely to be from
         a stationary point!  You must also supply a
         $HESS group.

VIBLVL = a flag to turn this option on (default=.FALSE.)

VIBENG = an array of energies (in units of multiples of
         the hv of each mode) to be imparted along each
         normal mode.  The default is to assign the zero
         point energy only, VIBENG(1)=0.5, 0.5, ..., 0.5.
         If given as a negative number, the initial
         direction of the velocity vector is along the
         reverse direction of the mode.  "Reverse" means
         the phase of the normal mode is chosen such that
         the largest magnitude component is a negative
         value.  An example might be VIBENG(4)=2.5 to add
         two quanta to mode 4, along with zero point
         energy in all modes.

                           * * *

         The next three pertain to initiating the DRC
         along a single normal mode of vibration.  No
         kinetic energy is assigned to the other modes.
         You must also supply a $HESS group.

NNM    = The number of the normal mode to which the initial
         kinetic energy is given.  The absolute value of NNM
         must be in the range 1, 2, ..., 3N-6.  If NNM is a
         positive/negative value, the initial velocity will
         lie in the forward/reverse direction of the mode.
         "Forward" means the largest component of the normal
         mode is a positive value.  (default=0)

ENM    = the initial kinetic energy given to mode NNM,
         in units of vibrational quanta hv, so the amount
         depends on mode NNM's vibrational frequency, v.
         If you prefer to impart an arbitrary initial
         kinetic energy to mode NNM, specify EKIN instead.
         (default = 0.0 quanta)

                           * * *

To summarize, there are five different ways to specify the
DRC trajectory:

   1. VEL vector with NVEL=.TRUE.  This is difficult to
      specify at your initial point, and so this option
      is mainly used when restarting your trajectory.
      The restart information is always in this format.
   2. VEL vector and EKIN with NVEL=.FALSE.  This will
      give a desired amount of kinetic energy in the
      direction of the velocity vector.
   3. VIBLVL and VIBENG selected, to give initial kinetic
      energy to all of the normal modes.
   4. NNM and ENM to give quanta to a single normal mode.
   5. NNM and EKIN to give arbitrary kinetic energy to
      a single normal mode.

                           * * *

       The most common use of the next two is to
       analyze a trajectory with respect to the
       minimum energy geometry the trajectory is
       traveling around.

NMANAL = a flag to select mapping of the mass-weighted
         Cartesian DRC coordinates and velocity (conjugate
         momentum) in terms of normal modes step by step.
         If you choose this option, you must supply both
         C0 and a $HESS group from the stationary point.
         (default=.FALSE.)

C0     = an array of the coordinates of the stationary
         point (the coordinates in $DATA might well be
         some other coordinates).  Give in the order
         x1,y1,z1,x2,y2,...

                           * * *

     The next option applies to all input paths which
     read a hessian: NMANAL, NNM, or VIBLVL.  After
     the translations and rotations have been dropped,
     the normal modes are renumbered 1, 2, ..., 3N-6.

HESSTS = a flag to say if the hessian corresponds to a
         transition state or a minimum.  This parameter
         controls deletion of the translation and rotation
         degrees of freedom, i.e. the default is to drop
         the first six "modes", while setting this flag
         on drops modes 2 to 7 instead. (default=.FALSE.)

                           * * *

    The final variables control the volume of output.
    Let F mean the first DRC point found in this run,
    and L mean the last DRC point of this run.

NPRTSM = summarize the DRC results every NPRTSM steps,
         to the file IRCDATA.  (default = 1)

NPRT   =  1  Print orbitals at all DRC points
          0  Print orbitals at F+L (default)
         -1  Never print orbitals

NPUN   =  2  Punch all orbitals at all DRC points
          1  Punch all orbitals at F+L, and occupied
             orbitals at DRC points between
          0  Punch all orbitals at F+L only (default)
         -1  Never punch orbitals

==========================================================

References:

J.J.P.Stewart, L.P.Davis, L.W.Burggraf,
    J.Comput.Chem. 8, 1117-1123 (1987)

S.A.Maluendes, M.Dupuis,  J.Chem.Phys. 93, 5902-5911(1990)

T.Taketsugu, M.S.Gordon,  J.Phys.Chem. 99, 8462-8471(1995)

T.Taketsugu, M.S.Gordon,  J.Phys.Chem. 99, 14597-604(1995)

T.Taketsugu, M.S.Gordon,  J.Chem.Phys. 103, 10042-9(1995)

T.Taketsugu, M.S.Gordon,  J.Chem.Phys. 104, 2834-40(1996)

M.S.Gordon, G.Chaban, T.Taketsugu
    J.Phys.Chem. 100, 11512-11525(1996)

==========================================================

$SURF group                  (relevant for RUNTYP=SURFACE)

    This group allows you to probe a potential energy
surface along a small grid of points.  Note that there is
no option to vary angles, only distances.  The scan can
be made for any SCFTYP, or for the MP2 or CI surface.

IVEC1  = an array of two atoms, defining a coordinate from
         the first atom given, to the second.

IGRP1  = an array specifying a group of atoms, which must
         include the second atom given in IVEC1.  The
         entire group will be translated (rigidly) along
         the vector IVEC1, relative to the first atom
         given in IVEC1.

ORIG1  = starting value of the coordinate, which may be
         positive or negative.  Zero corresponds to the
         distance given in $DATA.

DISP1  = step size for the coordinate.

NDISP1 = number of steps to take for this coordinate.

        There are no reasonable defaults for these
        keywords, so you should input all of them.
        ORIG1 and DISP1 should be given in Angstrom.

IVEC2, IGRP2, ORIG2, DISP2, NDISP2 = have the identical
meaning as their "1" counterparts, and permit you to make
a two dimensional map along two displacement coordinates.
If the "2" data are not input, the surface map proceeds in
only one dimension.

Note that properties are not computed at these points,
other than the energy.

==========================================================

$LOCAL group  (relevant for LOCAL=RUEDNBRG, BOYS, or POP)

    This group allows input of additional data to control
the localization methods.  If no input is provided, the
valence orbitals will be localized as much as possible,
while still leaving the wavefunction invariant.

PRTLOC = a flag to control supplemental printout.  The
         extra output is the rotation matrix to the
         localized orbitals, and, for the Boys method,
         the orbital centroids, for the Ruedenberg
         method, the coulomb and exchange matrices,
         for the population method, atomic populations.
         (default=.FALSE.)

MAXLOC = maximum number of localization cycles.  This
         applies to BOYS or POP methods only.  If the
         localization fails to converge, a different
         order of 2x2 pairwise rotations will be tried.
         (default=250)

CVGLOC = convergence criterion.  The default provides
         LMO coefficients accurate to 6 figures.
         (default=1.0E-6)

SYMLOC = a flag to restrict localization so that
         orbitals of different symmetry types are not
         mixed.  This option is not supported in all
         possible point groups.  The purpose of this
         option is to give a better choice for the
         starting orbitals for GVB-PP or MCSCF runs,
         without destroying the orbital's symmetry.
         This option is compatible with each of the
         3 methods of selecting the orbitals to be
         included.  (default=.FALSE.)

                                                    $LOCAL

    These parameters select the orbitals which are
    to be included in the localization.  You may
    select from FCORE, NOUTA/NOUTB, or NINA/NINB,
    but may choose only one of these.

FCORE  = flag to freeze all the chemical core orbitals
         present.   All the valence orbitals will be
         localized.  (default=.TRUE.)

                       * * *

NOUTA  = number of alpha orbitals to hold fixed in the
         localization.  (default=0)

MOOUTA = an array of NOUTA elements giving the numbers of
         the orbitals to hold fixed.  For example, the
         input NOUTA=2 MOOUTA(1)=8,13 will freeze only
         orbitals 8 and 13.  You must enter all the
         orbitals you want to freeze, including any cores.
         This variable has nothing to do with cows.

NOUTB =  number of beta orbitals to hold fixed in -UHF-
         localizations.  (default=0)

MOOUTB = same as MOOUTA, except that it applies to the
         beta orbitals, in -UHF- wavefunctions only.

                       * * *

NINA   = number of alpha orbitals which are to be
         included in the localization.  (default=0)

MOINA  = an array of NINA elements giving the numbers of
         the orbitals to be included in the localization.
         Any orbitals not mentioned will be frozen.

NINB   = number of -UHF- beta MOs in the localization.
         (default=0)

MOINB  = same as MOINA, except that it applies to the
         beta orbitals, in -UHF- wavefunctions only.

N.B.  Since Boys localization needs the dipole integrals,
      do not turn off dipole moment calculation in $ELMOM.

----- The following keywords are used for the localized
      charge distribution (LCD) energy decomposition.

EDCOMP = flag to turn on LCD energy decomposition.
         Note that this method is currently implemented
         for SCFTYP=RHF and ROHF and LOCAL=RUEDNBRG only.
         The SCF LCD forces all orbitals to be localized,
         overriding input on the previous page.  See also
         LMOMP2 in the $MP2 group.  (default = .FALSE.)

MOIDON = flag to turn on LMO identification and subsequent
         LMO reordering, and assign nuclear LCD automat-
         ically.  (default = .FALSE.)

DIPDCM = flag for LCD molecular dipole decomposition.
         (default = .FALSE.)

QADDCM = flag for LCD molecular quadrupole decomposition.
         (default = .FALSE.)

POLDCM = flag to turn on LCD polarizability decomposition.
         This method is implemented for SCFTYP=RHF or ROHF
         and LOCAL=BOYS or RUEDNBRG. (default=.FALSE.)

POLANG = flag to choose units of localized polarizability
         output. The default is Angstroms**3, while false
         will give Bohr**3.  (default=.TRUE.)

ZDO    = flag for LCD analysis of a composite wave function,
         given in a $VEC group of a van der Waals complex,
         within the zero differential overlap approximation.
         The MOs are not orthonormalized and the inter-
         molecular electron exchange energy is neglected.
         In addition, the molecular overlap matrix is printed
         out.  This is a very specialized option.
         (default = .FALSE.)

----- The remaining keywords can be used to define the
      nuclear part of an LCD.  They are usually used to
      rectify mistakes in the automatic definition
      made when MOIDON=.TRUE.  The index defining the
      LMO number then refers to the reordered list of LMOs.

NNUCMO = array giving the number of nuclei assigned to a
         particular LMO.

IJMO   = is an array of pairs of indices (I,J), giving
         the row (nucleus I) and column (orbital J)
         index of the entries in ZIJ and MOIJ.

MOIJ   = arrays of integers K, assigning nucleus K as the
         site of the Ith charge of LCD J.

ZIJ    = array of floating point numbers assigning a
         charge to the Ith charge of LCD J.

IPROT  = array of integers K, defining nucleus K as a
         proton.

DEPRNT = a flag for additional decomposition printing,
         such as pair contributions to various energy
         terms, and centroids of the Ruedenberg orbitals.
         (default = .FALSE.)

==========================================================


            * * * * * * * * * * * * * * * * * *
            For hints about localizations, and
            the LCD energy decomposition, see
            the 'further information' section.
            * * * * * * * * * * * * * * * * * *

==========================================================

$TWOEI group   (relevant for EDCOMP=.TRUE. in $LOCAL)

   Formatted transformed two-electron Coulomb and Exchange
integrals as punched during a LOCAL=RUEDNBRG run.  If this
group is present it will automaticall be read in during
such a run and the two-electron integrals do not have to
be re-transformed.  This group is especially useful for
EDCOMP=.TRUE. runs when the localization has to be repeated
for different definitions of nuclear LCDs.

==========================================================

$ELMOM group   (not required)

This group controls electrostatic moments calculation.

IEMOM  = 0 - skip this property
         1 - calculate monopole and dipole (default)
         2 - also calculate quadrupole moments
         3 - also calculate octupole moments

WHERE  = COMASS   - center of mass (default)
         NUCLEI   - at each nucleus
         POINTS   - at points given in $POINTS.

OUTPUT = PUNCH, PAPER, or BOTH (default)

IEMINT = 0 - skip printing of integrals (default)
         1 - print dipole integrals
         2 - also print quadrupole integrals
         3 - also print octupole integrals
        -2 - print quadrupole integrals only
        -3 - print octupole integrals only

    The quadrupole and octupole tensors on the printout
are formed according to the definition of Buckingham.
Caution: only the first nonvanishing term in the multi-
ipole charge expansion is independent of the coordinate
origin chosen, which is normally the center of mass.
==========================================================

$ELPOT group   (not required)

This group controls electrostatic potential calculation.

IEPOT = 0 skip this property (default)
        1 calculate electric potential

WHERE  = COMASS   - center of mass
         NUCLEI   - at each nucleus (default)
         POINTS   - at points given in $POINTS
         GRID     - at grid given in $GRID
         PDC      - at points controlled by $PDC.

OUTPUT = PUNCH, PAPER, or BOTH (default)

    This property is the electrostatic potential V(a) felt
by a test positive charge, due to the molecular charge
density.  A nucleus at the evaluation point is ignored.
If this property is evaluated at the nuclei, it obeys the
equation
     sum on nuclei(a)   Z(a)*V(a) = 2*V(nn) + V(ne).
The electronic portion of this property is called the
diamagnetic shielding.
==========================================================

$ELDENS group   (not required)

This group controls electron density calculation.

IEDEN  = 0 skip this property (default)
       = 1 compute the electron density.

MORB   = The molecular orbital whose electron density is
         to be computed.  If zero, the total density is
         computed.  (default=0)

WHERE  = COMASS   - center of mass
         NUCLEI   - at each nucleus (default)
         POINTS   - at points given in $POINTS
         GRID     - at grid given in $GRID

OUTPUT = PUNCH, PAPER, or BOTH (default)

IEDINT = 0 - skip printing of integrals (default)
         1 - print the electron density integrals

==========================================================

$ELFLDG group   (not required)

    This group controls electrostatic field and electric
field gradient calculation.

IEFLD  = 0 - skip this property (default)
         1 - calculate field
         2 - calculate field and gradient

WHERE  = COMASS   - center of mass
         NUCLEI   - at each nucleus (default)
         POINTS   - at points given in $POINTS

OUTPUT = PUNCH, PAPER, or BOTH (default)

IEFINT = 0 - skip printing these integrals (default)
         1 - print electric field integrals
         2 - also print field gradient integrals
        -2 - print field gradient integrals only

The Hellman-Feynman force on a nucleus is the nuclear
charge multiplied by the electric field at that nucleus.
The electric field is the gradient of the electric
potential, and the field gradient is the hessian of the
electric potential.  The components of the electric field
gradient tensor are formed in the conventional way, i.e.
see D.Neumann and J.W.Moskowitz.

==========================================================

$POINTS group   (not required)

    This group is used to input points at which properties
will be computed.  This first card in the group must
contain the string ANGS or BOHR, followed by an integer
NPOINT, the number of points to be used.  The next NPOINT
cards are read in free format, containing the X, Y, and Z
coordinates of each desired point.

==========================================================

$GRID group     (not required)

    This group is used to input a grid (plane through the
molecule) on which properties will be calculated.

ORIGIN(i) = coordinates of the lower left corner of
            the plot.
XVEC(i)   = coordinates of the lower right corner of
            the plot.
YVEC(i)   = coordinates of the upper left corner of
            the plot.
SIZE      = grid increment, default is 0.25.
UNITS     = units of the above four values, it can be
            either BOHR or ANGS (the default).

Note that XVEC and YVEC are not necessarily parallel to
the X and Y axes, rather they are the axes which you
desire to see plotted by the MEPMAP contouring program.

==========================================================



         * * * * * * * * * * * * * * * * * * * *
         For conversion factors, and references
         see the 'further information' section.
         * * * * * * * * * * * * * * * * * * * *

==========================================================

$PDC group               (relevant if WHERE=PDC in $ELPOT)

     This group determines the points at which to compute
the electrostatic potential, for the purpose of fitting
atomic charges to this potential.  Constraints on the fit
which determines these "potential determined charges" can
include the conservation of charge, the dipole, and the
quadrupole.

PTSEL  = determines the points to be used, choose from
         GEODESIC to use a set of points on several fused
               sphere van der Waals surfaces, with points
               selected using an algorithm due to Mark
               Spackman.  The results are similar to those
               from the Kollman/Singh method, but are
               less rotation dependent. (default)
         CONNOLLY to use a set of points on several fused
               sphere van der Waals surfaces, with points
               selected using an algorithm due to Michael
               Connolly.  This is identical to the method
               used by Kollman & Singh (see below)
         CHELPG to use a modified version of the CHELPG
               algorithm, which produces a symmetric
               grid of points for a symmetric molecule.

CONSTR = NONE   - no fit is performed.  The potential at
                  the points is instead output according
                  to OUTPUT in $ELPOT.
         CHARGE - the sum of fitted atomic charges is
                  constrained to reproduce the total
                  molecular charge. (default)
         DIPOLE - fitted charges are constrained to
                  exactly reproduce the total charge
                  and dipole.
         QUPOLE - fitted charges are constrained to
                  exactly reproduce the charge, dipole,
                  and quadrupole.

    Note: the number of constraints cannot exceed
    the number of parameters, which is the number
    of nuclei.  Planar molecules afford fewer
    constraint equations, namedly two dipole
    constraints and three quadrupole constraints,
    instead of three and five, repectively.

* * * the next 5 pertain to PTSEL=GEODESIC or CONNOLLY * * *

VDWSCL = scale factor for the first shell of VDW spheres.
         The default of 1.4 seems to be an empirical best
         value. Values for VDW radii for most elements up
         to Z=36 are internally stored.

VDWINC = increment for successive shells (default = 0.2).
         The defaults for VDWSCL and VDWINC will result
         in points chosen on layers at 1.4, 1.6, 1.8 etc
         times the VDW radii of the atoms.

LAYER  = number of layers of points chosen on successive
         fused sphere VDW surfaces (default = 4)

NFREQ  = flag for particular geodesic tesselation of
         points.  Only relevant if PTSEL=GEODESIC.
         Options are:
          (10*h + k)  for   {3,5+}h,k tesselations
         -(10*h + k)  for   {5+,3}h,k tesselations
         (of course both nh and nk must be less than 10,
         so NFREQ must lie within the range -99 to 99)
         The default value is NFREQ=30 (=03)

PTDENS = density of points on the surface of each scaled
         VDW sphere (in points per square au).  Only relevant
         if PTSEL=CONNOLLY.  Default is 0.28 per au squared,
         which corresponds to 1.0 per square Angstrom, the
         default recommended by Kollman & Singh.

   * * * the next two pertain to PTSEL=CHELPG * * *

RMAX   = maximum distance from any point to the closest
         atom.  (default=3.0 Angstroms)

DELR   = distance between points on the grid.
         (default=0.8 Angstroms)

MAXPDC = an estimate of the total number of points whose
         electrostatic potential will be included in the
         fit. (default=10000)

                       * * *

CENTER = an array of coordinates at which the moments were
         computed.

DPOLE  = the molecular dipole.

QPOLE  = the molecular quadrupole.

PDUNIT = units for the above values.  ANGS (default) will
         mean that the coordinates are in Angstroms, the
         dipole in Debye, and quadrupole in Buckinghams.
         BOHR implies atomic units for all 3.

  Note: it is easier to compute the moments in the
  current run, by setting IEMOM to at least 2 in
  $ELMOM.  However, you could fit experimental data,
  for example, by reading it in here.

==========================================================

     There is no unique way to define fitted atomic
charges.  Smaller numbers of points at which the electro-
static potential is fit, changes in VDW radii, asymmetric
point location, etc. all affect the results.  A useful
bibliography is

U.C.Singh, P.A.Kollman, J.Comput.Chem. 5, 129-145(1984)
L.E.Chirlain, M.M.Francl, J.Comput.Chem. 8, 894-905(1987)
R.J.Woods, M.Khalil, W.Pell, S.H.Moffatt, V.H.Smith,
   J.Comput.Chem. 11, 297-310(1990)
C.M.Breneman, K.B.Wiberg, J.Comput.Chem. 11, 361-373(1990)
K.M.Merz, J.Comput.Chem. 13, 749(1992)
M.A.Spackman, J.Comput.Chem. 17, 1-18(1996)

==========================================================

$MOLGRF group        (relevant only if you have MOLGRAPH)

   This option provides an interface for viewing orbitals
through a commercial package named MOLGRAPH, from Daikin
Industries.  Note that this option uses three disk files
which are not defined in the GAMESS execution scripts we
provide, since we don't use MOLGRAPH ourselves.  You will
need to define files 28, 29, 30, as generic names PRGRID,
COGRID, MOGRID, of which the latter is passed to MOLGRAPH.

GRID3D = a flag to generate 3D grid data.
         (default is .false.).

TOTAL  = a flag to generate a total density grid data.
         "Total" means the sum of the orbital densities
         given by NPLT array.  (default is .false.).

MESH   = numbers of grids.  You can use different numbers
         for three axes.  (default is MESH(1)=21,21,21).

BOUND  = boundary coordinates of a 3D graphical cell.  The
         default is that the cell is larger than the
         molecular skeleton by 3 bohr in all directions.
         E.g., BOUND(1)=xmin,xmax,ymin,ymax,zmin,zmax

NPLOTS = number of orbitals to be used to generate 3D grid
         data. (default is NPLOTS=1).

NPLT   = orbital IDs.  The default is 1 orbital only, the
         HOMO or SOMO.  If the LOCAL option is given in
         $CONTRL, localized orbital IDs should be given.
         For example, NPLT(1)=n1,n2,n3,...

CHECK  = debug option, printing some of the grid data.


If you are interested in graphics, look at the WWW page
for information about other graphics packages with GAMESS.

==========================================================

$STONE group      (optional)

    This group defines the expansion points for Stone's
distributed multipole analysis (DMA) of the electrostatic
potential.

    The DMA takes the multipolar expansion of each overlap
charge density defined by two gaussian primitives, and
translates it from the center of charge of the overlap
density to the nearest expansion point.  Some references
for the method are

    Stone, Chem.Phys.Lett. 83, 233 (1981)
    Price and Stone, Chem.Phys.Lett. 98, 419 (1983)
    Buckingham and Fowler, J.Chem.Phys. 79, 6426 (1983)
    Stone and Alderton, Mol.Phys. 56, 1047 (1985)

    The existence of a $STONE group in the input is what
triggers the analysis.  Enter as many lines as you wish,
in any order, terminated by a $END record.

----------------------------------------------------------

ATOM i name, where

      ATOM     is a keyword indicating that a particular
               atom is selected as an expansion center.
      i        is the number of the atom
      name     is an optional name for the atom. If not
               entered the name will be set to the name
               used in the $DATA input.

----------------------------------------------------------

ATOMS          is a keyword selecting all nuclei in the
               molecule as expansion points.  No other
               input on the line is necessary.

----------------------------------------------------------

BONDS          is a keyword selecting all bond midpoints
               in the molecule as expansion points.  No
               other input on the line is necessary.

----------------------------------------------------------

BOND i j name, where

      BOND     is a keyword indicating that a bond mid-
               point is selected as an expansion center.
      i,j      are the indices of the atoms defining the
               bond, corresponding to two atoms in $DATA.
      name     an optional name for the bond midpoint.
               If omitted, it is set to 'BOND'.

----------------------------------------------------------

CMASS          is a keyword selecting the center of mass
               as an expansion point.  No other input on
               the line is necessary.

----------------------------------------------------------

POINT x y z name, where

      POINT    is a keyword indicating that an arbitrary
               point is selected as an expansion point.
      x,y,z    are the coordinates of the point, in Bohr.
      name     is an optional name for the expansion
               point.  If omitted, it is set to 'POINT'.

==========================================================

The second and third moments on the printout can be
converted to Buckingham's tensors by formula 9 of
  A.D.Buckingham, Quart.Rev. 13, 183-214 (1959)
These can in turn be converted to spherical tensors
by the formulae in the appendix of
  S.L.Price, et al.  Mol.Phys. 52, 987-1001 (1984)

==========================================================

$MOROKM group               (relevant for RUNTYP=MOROKUMA)

    This group controls how the supermolecule input in the
$DATA group is divided into two or more monomers.  Both
the supermolecule and its constituent monomers must be
well described by RHF wavefunctions.

MOROKM = a flag to request Morokuma-Kitaura decomposition.
         (default is .TRUE.)

RVS    = a flag to request "reduced variation space"
         decomposition.  This differs from the Morokuma
         option, and one or the other or both may be
         requested in the same run.  (default is .FALSE.)

BSSE   = a flag to request basis set superposition error
         be computed.  You must ensure that CTPSPL is
         selected.  This option applies only to MOROKM
         decompositions, as a basis superposition error is
         automatically generated by the RVS scheme.  This
         is not the full Boys counterpoise correction, as
         explained in the reference.  (default is .FALSE.)

                           * * *

IATM   = An array giving the number of atoms in each of
         the monomer.  Up to ten monomers may be defined.
         Your input in $DATA must have all the atoms in
         the first monomer defined before the atoms in the
         second monomer, before the third monomer...  The
         number of atoms belonging to the final monomer
         can be omitted.  There is no sensible default for
         IATM, so don't omit it from your input.

ICHM   = An array giving the charges of the each monomer.
         The charge of the final monomer may be omitted,
         as it is fixed by ICH in $CONTRL, which is the
         total charge of the supermolecule.  The default
         is neutral monomers, ICHM(1)=0,0,0,...

EQUM   = a flag to indicate all monomers are equivalent
         by symmetry (in addition to containing identical
         atoms). If so, which is not often true, then only
         the unique computations will be done.
         (default is .FALSE.)

CTPSPL = a flag to decompose the interaction energy into
         charge transfer plus polarization terms.  This
         is most appropriate for weakly interacting
         monomers. (default is .TRUE.)

CTPLX  = a flag to combine the CT and POL terms into a
         single term.  If you select this, you might want
         to turn CTPSPL off to avoid the extra work that
         that decomposition entails, or you can analyze
         both ways in the same run (default=.FALSE.)

RDENG  = a flag to enable restarting, by reading the
         lines containing "FINAL ENERGY" from a previous
         run.  The $ENERGY group is single lines read
         under format A16,F20.10 containing the E, and a
         card $END to complete.  The 16 chars = anything.
         (default is .FALSE.)

==========================================================

The present implementation has some quirks:

1. The initial guess of the monomer orbitals is not
   controlled by $GUESS.  The program first looks for a
   $VEC1, $VEC2, ... group for each monomer.  If they
   are found, they will be MOREAD.  If any of these are
   missing, the guess for that monomer will be constructed
   by HCORE.   Check your monomer energies carefully!  The
   initial guess orbitals for the supermolecule are formed
   by a block diagonal matrix of the monomer orbitals.
2. The use of symmetry is turned off internally.
3. There is no direct SCF option.  File ORDINT will be a
   full C1 list of integrals.  File AOINTS will contain
   whatever subset of these is needed for each particular
   decomposition step.  So extra disk space is needed
   compared to RUNTYP=ENERGY.
4. This kind of run applies only to ab initio cases.
5. This kind of run will work in parallel.

References:

C.Coulson  in "Hydrogen Bonding", D.Hadzi, H.W.Thompson,
   Eds., Pergamon Press, NY, 1957, pp 339-360.
C.Coulson  Research, 10, 149-159 (1957).
K.Morokuma  J.Chem.Phys. 55, 1236-44 (1971).
K.Kitaura, K.Morokuma  Int.J.Quantum Chem. 10, 325 (1976).
K.Morokuma, K.Kitaura  in "Chemical Applications of
   Electrostatic Potentials", P.Politzer,D.G.Truhlar, Eds.
   Plenum Press, NY, 1981, pp 215-242.
The method coded is the newer version described in the
latter two papers.  Note that the CT term is computed
separately for each monomer, as described in the words
below equation 16 of the 1981 paper, not simultaneously.

Reduced Variational Space:
W.J.Stevens, W.H.Fink, Chem.Phys.Lett. 139, 15-22(1987).

A comparison of the RVS and Morokuma decompositions can
be found in the review article: "Wavefunctions and
Chemical Bonding" M.S.Gordon, J.H.Jensen in "Encyclopedia
of Computational Chemistry", volume 5, P.V.R.Schleyer,
editor, John Wiley and Sons, Chichester, 1998.

BSSE during Morokuma decomposition:
R.Cammi, R.Bonaccorsi, J.Tomasi
Theoret.Chim.Acta 68, 271-283(1985).

The present implementation:
"Energy decomposition analysis for many-body interactions,
 and application to water complexes"
W.Chen, M.S.Gordon   J.Phys.Chem. 100, 14316-14328(1996)

==========================================================

$FFCALC group                 (relevant for RUNTYP=FFIELD)

    This group permits the study of the influence of an
applied electric field on the wavefunction.  The most
common finite field calculation applies a sequence of
fields to extract the linear polarizability and first and
second order hyperpolarizability.  The method is general,
and so works for all ab initio wavefunctions in GAMESS.

EFIELD      = applied electric field strength
              (default=0.001 a.u.)

IAXIS and JAXIS specify the orientation of the applied
                field.  1,2,3 mean x,y,z respectively.
                The default is IAXIS=3 and JAXIS=0.

  If IAXIS=i and JAXIS=0, the program computes alpha(ii),
  beta(iii), and gamma(iiii) from the energy changes, and
  a few more components from the dipole changes.  Five
  wavefunction evaluations are performed.

  If IAXIS=i and JAXIS=j, the program computes the cross
  terms beta(ijj), beta(iij), and gamma(iijj) from the
  energy changes, and a few more components from the
  dipole changes.  This requires nine evaluations of the
  wavefunction.

AOFF        = a flag to permit evaluation of alpha(ij)
              when the dipole moment is not available.
              This is necessary only for MP2, and means
              the off-axial calculation will do 13, not
              9 energy evaluations.  Default=.FALSE.

SYM         = a flag to specify when the fields to be
              applied along the IAXIS and/or JAXIS (or
              according to EONE below) do not break the
              molecular symmetry.  Since most fields do
              break symmetry, the default is .FALSE.

ONEFLD      = a flag to specify a single applied field
              calculation will be performed.  Only the
              energy and dipole moment under this field
              are computed.  If this option is selected,
              only SYM and EONE input is heeded.  The
              default is .FALSE.

EONE        = an array of the three x,y,z components of
              the single applied field.

There are notes on RUNTYP=FFIELD on the next page.

    Finite field calculations require large basis sets,
and extraordinary accuracy in the wavefunction.  To
converge the SCF to many digits is sometimes problematic,
but we suggest you use the input to increase integral
accuracy and wavefunction convergence, for example

   $CONTRL ICUT=20 ITOL=30 INTTYP=HONDO $END
   $SCF    NCONV=10 FDIFF=.FALSE. $END

    In many cases, the applied fields will destroy the
molecular symmetry.  This means the integrals are
calculated once with point group symmetry to do the
initial field free wavefunction evaluation, and then again
with point group symmetry turned off.  If the fields
applied do not destroy symmetry, you can avoid this second
calculation of the integrals by SYM=.TRUE.  This option
also permits use of symmetry during the applied field
wavefunction evaluations.

    Examples of fields that do not break symmetry are a
Z-axis field for an axial point group which is not
centrosymmetric (i.e. C2v).  However, a second field in
the X or Y direction does break the C2v symmetry.
Application of a Z-axis field for benzene breaks D6h
symmetry.  However, you could enter the group as C6v in
$DATA while using D6h coordinates, and regain the prospect
of using SYM=.TRUE.  If you wanted to go on to apply a
second field for benzene in the X direction, you might
want to enter Cs in $DATA, which will necessitate the
input of two more carbon and hydrogen atom, but recovers
use of SYM=.TRUE.

Reference: H.A.Kurtz, J.J.P.Stewart, K.M.Dieter
           J.Comput.Chem.  11, 82-87 (1990).

    For analytic computation of static and also frequency
dependent NLO proerties, for closed shell cases, see the
$TDHF group.

==========================================================

$TDHF group       (relevant for SCFTYP=RHF if RUNTYP=TDHF)

    This group permits the analytic calculation of various
static and/or frequency dependent polarizabilities, with
an emphasis on important NLO properties such as second and
third harmonic generation.  The method is programmed only
for closed shell wavefunctions, at the semi-empirical or
ab initio level.  Ab initio calculations may be direct SCF,
or parallel, if desired.

    Because the Fock matrices computed during the time-
dependent Hartree-Fock CPHF are not symmetric, you may not
use symmetry.  You must enter NOSYM=1 in $CONTRL!

    For a more general numerical approach to the static
properties, see $FFCALC.

NFREQ  = Number of frequencies to be used. (default=1)

FREQ   = An array of energy values in atomic units.  For
         example: if NFREQ=3 then FREQ(1)=0.0,0.1,0.25.
         By default, only the static polarizabilities are
         computed.  (default is freq(1)=0.0)

    The conversion factor from Hartree to wave
    numbers is 219,474.6, and the wavelength is
    given (in nm) by 45.56/FREQ.

MAXITA = Maximum number of iterations for an alpha
         computation. (default=100)

MAXITU = Maximum number of iterations in the second order
         correction calculation.  This applies to iterative
         beta values and all gammas. (default=100)

ATOL   = Tolerance for convergence of first-order results.
         (default=1.0d-05)

BTOL   = Tolerance for convergence of second-order results.
         (default=1.0d-05)

RETDHF = a flag to choose starting points for iterative
         calculations from best previous results.
         (default=.true.)

* * * the following NLO properties are available  * * *

BSHG   = Calculate beta for second harmonic generation.

BEOPE  = Calculate beta for electrooptic Pockels effect.

BOR    = Calculate beta for optical rectification.

GTHG   = Calculate gamma for third harmonic generation.

GEFISH = Calculate gamma for electric-field induced
         second harmonic generation.

GIDRI  = Calculate gamma for intensity dependent
         refractive index.

GOKE   = Calculate gamma for optical Kerr effect.

    These will be computed only if a nonzero energy is
requested.  The default for each flag is .TRUE., and they
may be turned off individually by setting some .FALSE.
Note however that the program determines the best way to
calculate them.  For example, if you wish to have the SHG
results but no gamma results are needed, the SHG beta will
be computed in a non-iterative way from alpha(w) and
alpha(2w).  However if you request the computation of the
THG gamma, the second order U(w,w) results are needed and
an iterative SHG calculation will be performed whether
you request it or not, as it is a required intermediate.

Reference:
S.P.Karna, M.Dupuis J.Comput.Chem.  12, 487-504 (1991).
P.Korambath, H.A.Kurtz, in "Nonlinear Optical Materials",
ACS Symposium Series 628, S.P.Karna and A.T.Yeates, Eds.
pp 133-144, Washington DC, 1996.

Review: D.P.Shelton, J.E.Rice, Chem.Rev. 94, 3-29(1994).

==========================================================

$EFRAG group  (optional)

   This group gives the name and position of one or more
effective fragment potentials.  It consists of a series of
free format card images, which may not be combined onto a
single line!  The position of a fragment is defined by
giving any three points within the fragment, relative to
the ab initio system defined in $DATA, since the effective
fragments have a frozen internal geometry.  All other
atoms within the fragment are defined by information in
the $FRAGNAME group.

----------------------------------------------------------

-1-   a line containing one or more of these options:

     COORD   =CART     selects use of Cartesians coords
                       to define the fragment position at
                       line -3-.  (default)
             =INT      selects use of Z-matrix internal
                       coordinates at line -3-.
     POLMETHD=SCF      indicates the induced dipole for
                       each fragment due to the ab initio
                       electric field and other fragment
                       fields is updated only once during
                       each SCF iteration.
             =FRGSCF   requests microiterations during
                       each SCF iteration to make induced
                       dipoles due to ab initio and other
                       fragment fields self consistent
                       amoung the fragments.  (default)
                       Both methods converge to the same
                       dipolar interaction.
     POSITION=OPTIMIZE Allows full optimization within the
                       ab initio part, and optimization of
                       the rotational and translational
                       motions of each fragment. (default)
             =FIXED    Allows full optimization of the
                       ab initio system, but freezes the
                       position of the fragments.  This
                       makes sense only with two or more
                       fragments, as what is frozen is the
                       fragments' relative orientation.
             =EFOPT    the same as OPTIMIZE, but if the
                       fragment gradient is large, up to
                       5 geometry steps in which only the
                       fragments move may occur, before
                       the geometry of the ab initio piece
                       is relaxed.  This may save time by
                       reusing the two electron integrals
                       for the ab initio system.

Input a blank line if all the defaults are acceptable.

----------------------------------------------------------

-2-  FRAGNAME=XXX

XXX is the name of the fragment whose coordinates are to
be given next.  All other information defining the
fragment is given in a supplemental $XXX group, which is
referred to below as a $FRAGNAME group.

A RHF/DZP EFP for water is internally stored in GAMESS.
Choose FRAGNAME=H2OEF2 to look up this numerical data,
and then skip the input of $H2OEF2 and $FRGRPL groups.

----------------------------------------------------------

-3-   NAME, X, Y, Z                           (COORD=CART)
      NAME, I, DISTANCE, J, BEND, K, TORSION  (COORD=INT)

NAME     = the name of a fragment point.  The name used
           here must match one of the points in $FRAGNAME.

X, Y, Z  = Cartesian coordinates defining the position of
           this fragment point RELATIVE TO THE COORDINATE
           ORIGIN used in $DATA.  The choice of units is
           controlled by UNITS in $CONTRL.

I, DISTANCE, J, BEND, K, TORSION = the usual Z-matrix
           connectivity internal coordinate definition.
           The atoms I, J, K must be atoms in the ab
           initio system from in $DATA, or fragment points
           already defined in the current fragment or
           previously defined fragments.

Line -3- must be given a total of three times to define
this fragment's position.

----------------------------------------------------------

Repeat lines -2- and -3- to enter as many fragments as you
desire, and then end the group with a $END line.

Note that it is quite typical to repeat the same fragment
name at line -2-, to use the same fragment system at many
different positions.

==========================================================

        * * * * * * * * * * * * * * * * * * * * *
        For tips on effective fragment potentials
          see the 'further information' section
        * * * * * * * * * * * * * * * * * * * * *

==========================================================

              (required for each FRAGNAME given in $EFRAG)
$FRAGNAME group

   This group gives all pertinent information for a given
effective fragment potential (EFP).  This information
falls into three categories:
     electrostatic (distributed multipoles, screening)
     distributed polarizabilities
     exchange repulsion
It is input using several different subgroups, which
should be given in the order shown below.  Each subgroup
is specified by a particular name, and is terminated by
the word STOP.  You may omit any of the subgroups to omit
that term from the EFP.  All values are given in atomic
units.

To input monopoles,             follow input sequence -EM-
To input dipoles,               follow input sequence -ED-
To input quadrupoles,           follow input sequence -EQ-
To input octupoles,             follow input sequence -EO-
To input screening parameters,  follow input sequence -ES-
To input polarizable points,    follow input sequence -P-
To input repulsive points,      follow input sequence -R-

----------------------------------------------------------

-1-   a single descriptive title card
----------------------------------------------------------

-2-   COORDINATES

COORDINATES signals the start of the subgroup containing
the multipolar expansion terms (charges, dipoles, ...).
Optionally, one can also give the coordinates of the
polarizable points, or centers of exchange repulsion.

-3-   NAME, X, Y, Z, WEIGHT, ZNUC

NAME is a unique string identifying the point.
X, Y, Z are the Cartesian coordinates of the point.
WEIGHT and ZNUC are the atomic mass and nuclear charge,
and are given only for the points which are nuclei.

Typically the true nuclei will appear twice, once for
defining the positive nuclear charge and its screening,
and a second time for defining the electronic distributed
multipoles.

Repeat line -3- for each expansion point, and terminate
the list with a "STOP".
----------------------------------------------------------

-EM1-  MONOPOLES

MONOPOLES signals the start of the subgroup containing
the electronic and nuclear monopoles.

-EM2-  NAME, CHARGE

NAME must match one given in the COORDINATES subgroup.
CHARGE = nuclear or electronic monopole at this point.

Repeat -EM2- to define all desired charges.
Terminate this subgroup with a "STOP".
----------------------------------------------------------

-ED1-  DIPOLES

DIPOLES signals the start of the subgroup containing the
dipolar part of the multipolar expansion.

-ED2-  NAME, MUX, MUY, MUZ

NAME must match one given in the COORDINATES subgroup.
MUX, MUY, MUZ are the components of the electronic dipole.

Repeat -ED2- to define all desired dipoles.
Terminate this subgroup with a "STOP".
----------------------------------------------------------

-EQ1-  QUADRUPOLES

QUADRUPOLES signals the start of the subgroup containing
the quadrupolar part of the multipolar expansion.

-EQ2-  NAME, XX, YY, ZZ, XY, XZ, YZ

NAME must match one given in the COORDINATES subgroup.
XX, YY, ZZ, XY, XZ, and YZ are the components of the
electronic quadrupole moment.

Repeat -EQ2- to define all desired quadrupoles.
Terminate this subgroup with a "STOP".
----------------------------------------------------------

-EO1-  OCTUPOLES

OCTUPOLES signals the start of the subgroup containing
the octupolar part of the multipolar expansion.

-EO2-  NAME, XXX, YYY, ZZZ, XXY, XXZ,
             XYY, YYZ, XZZ, YZZ, XYZ

NAME must match one given in the COORDINATES subgroup.
XXX, ...  are the components of the electronic octupole.

Repeat -EO2- to define all desired octupoles.
Terminate this subgroup with a "STOP".
----------------------------------------------------------

-ES1-  SCREEN

SCREEN signals the start of the subgroup containing the
screening terms (A*exp[-B*r**2]) for the distributed
multipoles, which account for charge penetration effects.

-ES2-  NAME, A, B

NAME must match one given in the COORDINATES subgroup.
A, B are the parameters of the Gaussian screening term.

Repeat -ES2- to define all desired screening points.
Terminate this subgroup with a "STOP".
----------------------------------------------------------

-P1-  POLARIZABLE POINTS

POLARIZABLE POINTS signals the start of the subgroup
containing the distributed polarizability tensors, and
their coordinates.

-P2-  NAME, X, Y, Z

NAME gives a unique identifier to the location of this
polarizability tensor.  It might match one of the points
already defined in the COORDINATES subgroup, but often
does not.  Typically the distributed polarizability
tensors are located at the centroids of localized MOs.

X, Y, Z are the coordinates of the polarizability point.
They should be omitted if NAME did appear in COORDINATES.
The units are controlled by UNITS= in $CONTRL.

-P3-  XX, YY, ZZ, XY, XZ, YZ, YX, ZX, ZY

XX, ... are components of the distributed polarizability,
which is not a symmetric tensor.  XY means dMUx/dFy, where
MUx is a dipole component, and Fy is a component of an
applied field.

Repeat -P2- and -P3- to define all desired polarizability
tensors, and terminate this subgroup with a "STOP".
----------------------------------------------------------

-R1-  REPULSIVE POTENTIAL

REPULSIVE POTENTIAL signals the start of the subgroup
containing the fitted exchange repulsion potential, for
the interaction between the fragment and the ab initio
part of the system.  This term also accounts for charge
transfer effects.  The term has the form

       N
      sum   C * exp[-D  * r**2]
       i     i        i


-R2-  NAME, X, Y, Z, N

NAME may match one given in the COORDINATES subgroup,
but need not.  If NAME does not match one of the
known points, you must give its coordinates X, Y, and
Z, otherwise omit these three values.  N is the total
number of terms in the fitted repulsive potential.

-R3-  C, D

These two values define the i-th term in the repulsive
potential.  Repeat line -R3- for all N terms.

Repeat -R2- and -R3- to define all desired repulsive
potentials,  and terminate this subgroup with a "STOP".

==========================================================

The entire $FRAGNAME group is terminated by a " $END".

==========================================================

$FRGRPL group

This group defines the inter-fragment repulsive potential,
which consists primarily of exchange repulsions but also
includes charge transfer.  Note that the functional form
used for the fragment-fragment repulsion differs from
that used for the ab initio-fragment repulsion, which is
defined in the $FRAGNAME group.  The form of the potential
is
       N
      sum   A * exp[-B * r]
       i     i        i

----------------------------------------------------------

-1-  PAIR=FRAG1 FRAG2

specifies which two fragment repulsions are being defined.
$FRAGNAME input for the two names FRAG1 and FRAG2 must
have been given.
----------------------------------------------------------

-2-  NAME1 NAME2 A B
            *or*
     NAME1 NAME2 'EQ' NAME3 NAME4

NAME1 must be one of the "NAME" points defined in the
$FRAG1 group's COORDINATE section.  Similarly NAME2 must
be a point from the $FRAG2 group.  In addition, NAME1 or
NAME2 could be the keyword CENTER, indicating the center
of mass of the fragment.

A and B are the parameters of the fitted repulsive
potential.

The second form of the input allows equal potential fits
to be used.  The syntax implies that the potential between
the points NAME1 and NAME2 should be taken the same as the
potential previously given in this group for the pair of
points NAME3 and NAME4.

If there are NPT1 points in FRAG1, and NPT2 points in
FRAG2, input line -2- should be repeated NPT1*NPT2 times.
Terminate the pairs of potentials with a "STOP" card.
Any pairs which you omit will be set to zero interaction.

Typically the number of points on which fitted potentials
might be taken to be all the nuclei in a fragment, plus
the center of mass.
----------------------------------------------------------

Repeat lines -1- and -2- for all pairs of fragments, then
terminate the group with a $END line.
==========================================================

$PCM group                                      (optional)

   This group controls solvent effect computations using
the Polarizable Continuum Method.  If this group is found
in the input file, a PCM computation is performed.  The
default calculation, chosen by selecting only the SOLVNT
keyword, is to compute the electrostatic free energy.
Appropriate numerical constants are provided for a wide
range of solvents.  Additional keywords allow for more
sophisticated computations, namely cavitation, repulsion,
and dispersion free energies.  The methodology for these
is general, but only numerical constants for water are
provided.  There is additional information on PCM in the
References chapter of this manual.

--- the first set of parameters controls the computation:
        ICOMP, ICAV, IDISP, IREP, IDP, and IFIELD.

ICOMP  = Renormalization procedure for induced charges.
         Gradient runs require ICOMP be 0 or 2 only.
       = 0 No.
       = 1 Yes, each charge is corrected in proportion
           to the area of the tessera to which it belongs.
       = 2 Yes, using the same factor for all tesserae.
           (default)
       = 3 Yes, with explicit consideration of the
           portion of solute electronic charge outside
           the cavity, by the method of Mennucci and
           Tomasi.  See the $NEWCAV group.

ICAV   = At the end of the run, calculate the cavitation
         energy, by the method of Pierotti and Claverie:
       = 0 skip the computation (default)
       = 1 perform the computation.

  If ICAV=1, the following parameter is relevant:

TABS   = the absolute temperature, in units K.
         (default=298.0)

     There are two procedures for the calculation
     of the repulsion and dispersion free energy.
     IDISP is incompatible with IREP and IDP.

IDISP  = Calculation of both dispersion and repulsion
         free energy through the empirical method of
         Floris and Tomasi.
       = 0 skip the computation (default)
       = 1 perform the computation.  See $DISREP group.

  The next two options add repulsive and dispersive terms
  to the solute hamiltonian, in an ab initio manner, by
  the method of Amovilli and Mennucci.

IREP   = Calculation of repulsion free energy
       = 0 skip the computation (default)
       = 1 perform the computation.  See $NEWCAV group.

IDP    = Calculation of dispersion free energy
       = 0 skip the computation (default)
       = 1 perform the computation.  See $DISBS group.

  If IDP=1, then three additional parameters must be
  defined.  The two solvent values correspond to water,
  and therefore these must be input for other solvents.

WA     = solute average transition energy.  This is
         computed from the orbital energies for RHF,
         but must be input for MCSCF runs.
         (default=1.10)
WB     = ionization potential of solvent, in Hartrees.
         (default=0.451)
ETA2   = square of the zero frequency refractive index
         of the solvent.  (default=1.75)

IFIELD = At run end, calculate the electric potential
         and electric field generated by the apparent
         surface charges.
       = 0 skip the computation (default)
       = 1 on nuclei
       = 2 on a planar grid

  If IFIELD=2, the following data must be input:

AXYZ,BXYZ,CXYZ = each defines three components of the
                 vertices of the plane where the reaction
                 field is to be computed (in Angstroms)
      A ===> higher left corner of the grid
      B ===> lower left corner of the grid
      C ===> higher right corner of the grid
NAB = vertical subdivision (A--B edge) of the grid
NAC = horizontal subdivision (A--C edge) of the grid.

IPRINT = 0 normal printing (default)
       = 1 turns on debugging printout

--- the next group of keywords defines the solvent

SOLVNT = keyword naming the solvent of choice.  The eight
         numerical constants defining the solvent are
         internally stored for the following:
             WATER (or H2O)
             CH3OH
             C2H5OH
             CLFORM (or CHCl3)
             METHYCL (or CH2Cl2)
             12DCLET (or C2H4Cl2)
             CTCL (or CCl4)
             BENZENE (or C6H6)
             TOLUENE (or C6H5CH3)
             CLBENZ (or C6H5Cl)
             NITMET (or CH3NO2)
             NEPTANE (or C7H16)
             CYCHEX (or C6H12)
             ANILINE (or C6H5NH2)
             ACETONE (or CH3COCH3)
             THF
             DMSO (or DMETSOX)
         The default solvent name is
             INPUT
         which indicates you will specify your solvent by
         giving the following 8 numerical values:

RSOLV  = the solvent radius, in units Angstrom
EPS    = the dielectric constant
EPSINF = the dielectric constant at infinite frequency.
         This value must be given only for RUNTYP=TDHF,
         if the external field frequency is in the optical
         range and the solvent is polar; in this case the
         solvent response is described by the electronic
         part of its polarization.  Hence the value of the
         dielectric constant to be used is that evaluated
         at infinite frequency, not the static one (EPS).
         For nonpolar solvents, the difference between
         the two is almost negligible.
TCE    = the thermal expansion coefficient, in units 1/K
VMOL   = the molar volume, in units ml/mole
STEN   = the surface tension, in units dyne/cm
DSTEN  = the thermal coefficient of log(STEN)
CMF    = the cavity microscopic coefficient

Values for TCE, VMOL, STEN, DSTEN, CMF need to be given
only for the case ICAV=1.  Input of any or all of these
values will override the internally stored value.

--- the next set of keywords defines the molecular cavity

NESFP  = the number of initial spheres.
         (default = number of atoms in solute molecule)

ICENT  = option for definition of initial spheres.
       = 0 centers spheres on each nucleus.  (default)
       = 1 sphere centers XE, YE, ZE and radii RIN will be
           specified explicitly in $PCMCAV.

   The cavity generation algorithm may use additional
   spheres to smooth out sharp grooves, etc.  The
   following parameters control how many extra spheres
   are generated:

OMEGA and FRO = GEPOL parameters for the creation of the
         `added spheres' defining the solvent accessible
         surface. When an excessive number of spheres is
         created, which may cause problems of convergence,
         the value of OMEGA and/or FRO must be increased.
         For example, OMEGA from 40 to 50 ... up to 90,
                      FRO from 0.2 ... up to 0.7.
         (defaults are OMEGA=40.0, FRO=0.7)

RET    = minimum radius (in A) of the added spheres.
         Increasing RET decreases the number of added
         spheres.  A value of 100.0 inhibits the addition
         of spheres.  (default=0.2)

==========================================================

$PCMCAV group                                   (optional)

   This group controls generation of the cavity holding
the solute during Polarizable Continuum Method runs.
The cavity is a union of spheres, according to ICENT and
associated input values given in $PCM.  The data given
here must be given in Angstrom units.

XE,YE,ZE = arrays giving the coordinates of the spheres.
    if ICENT=0, the atomic positions will be used.
    if ICENT=1, you must supply NESFP values here.

RIN = an array giving the sphere radii.
    if ICENT=0, the program will look up the internally
                stored van der Waals radius for:  H,He,
                   B,C,N,O,F,Ne,   Na,Al,Si,P,S,Cl,Ar,
                   K,As,Se,Br,Kr,  Rb,Sb,Te,I,  Cs,Bi
                Data for other elements is not tabulated.
    if ICENT=1, give NESFP values.

ALPHA = an array of scaling factors, for the definition of
        the solvent accessible surface.  If only the first
        value is given, all radii are scaled by the same
        factor.  (default is ALPHA(1)=1.2)

Example: Suppose the 4th atom in your molecule is Fe, but
         all other atoms have van der Waals radii.  You
         decide a good guess for Fe is twice the covalent
         radius:  $PCMCAV RIN(4)=2.33 $END

The source for the van der Waals radii is "The Elements",
2nd Ed., John Emsley, Clarendon Press, Oxford, 1991,
except that for C,N,O, the U.Pisa's experience with the
best radii for PCM treatment of singly bonded C,N,O atoms
is used instead.  The radii for a few transition metals
are given by A.Bondi, J.Phys.Chem. 68, 441-451(1968).

==========================================================

$NEWCAV group                                   (optional)

   This group controls generation of the "escaped charge"
cavity, used when ICOMP=3 or IREP=1 in $PCM.  This cavity
is used only to calculate the fraction of the solute
electronic charge escapes from the original cavity.

IPTYPE = choice for tessalation of the cavity's spheres.
       = 1 uses a tetrahedron
       = 2 uses a pentakisdodecahedron (default)

ITSNUM = m, the number of tessera to use on each sphere.
       if IPTYPE=1, input m=30*(n**2), with n=1,2,3 or 4
       if IPTYPE=2, input m=60*(n**2), with n=1,2,3 or 4
       (default is 60)

   *** the next three parameters pertain to IREP=1 ***

RHOW   = density, relative to liquid water (default = 1.0)

PM     = molecular weight (default = 18.0)

NEVAL  = number of valence electrons on solute (default=8)

The defaults for RHOW, PM, and NEVAL correspond to water,
and therefore must be correctly input for other solvents.

==========================================================

$DISBS group                                    (optional)

   This group defines auxiliary basis functions used to
evaluate the dispersion free energy by the method of
Amovilli and Mennucci.  These functions are used only for
the dispersion calculation, and thus have nothing to do
with the normal basis given in $BASIS or $DATA.  If the
input group is omitted, only the normal basis is used for
the IDP=1 dispersion energy.

NADD   = the number of added shells

XYZE   = an array giving the x,y,z coordinates (in bohr)
         of the center, and exponent of the added shell,
         for each of the NADD shells.

NKTYPE = an array giving the angular momenta of the shells

An example placing 2s,2p,2d,1f on one particular atom,

 $DISBS  NADD=7 NKTYP(1)= 0 0 1 1 2 2 3
         XYZE(1)=2.9281086   0.0  .0001726   0.2
                 2.9281086   0.0  .0001726   0.05
                 2.9281086   0.0  .0001726   0.2
                 2.9281086   0.0  .0001726   0.05
                 2.9281086   0.0  .0001726   0.75
                 2.9281086   0.0  .0001726   0.2
                 2.9281086   0.0  .0001726   0.2  $END

==========================================================

$DISREP group                                   (optional)

   This group controls evaluation of the dispersion and
repulsion energies by the empirical method of Floris and
Tomasi.  The group must be given with IDISP=1 in $PCM.
The two options are controlled by ICLAV and ILJ, only one
of which should be selected.

ICLAV = selects Claverie's disp-rep formalism.
      = 0 skip computation.
      = 1 Compute the solute-solvent disp-rep interaction
          as a sum over atom-atom interactions through a
          Buckingham-type formula (R^-6 for dispersion,
          exp for repulsion).  (default)
          Ref: Pertsin-Kitaigorodsky "The atom-atom
               potential method", page 146.

ILJ   = selects a Lennard-Jones formalism.
      = 0 skip computation. (default)
      = 1 solute atom's-solvent molecule interaction is
          modeled by Lennard-Jones type potentials, R^-6
          for dispersion, R^-12 for repulsion).

---- the following data must given for ICLAV=1:

RHO   = solvent numeral density
N     = number of atom types in the solvent molecule
NT    = an array of the number of atoms of each type in a
        solvent molecule
RDIFF = distances between the first atoms of each type
        and the cavity
DK,RW = parameters of atom-atom interactions

The defaults are chosen for water,
   RHO=3.348D-02
   N=2
   NT(1)=2,1
   RDIFF(1)=1.20,1.50
   DKT(1)=1.0,1.36
   RWT(1)=1.2,1.5

---- the following data must given for ILJ=1:

RHO   = solvent numeral density
EPSI  = an array of energy constants referred to each atom
        of the solute molecule.
SIGMA = an array of typical distances, relative to each
        solute atom

==========================================================

$SCRF group                                     (optional)

    The presence of this group in the input turns on the
use of the Kirkwood-Onsager spherical cavity model for the
study of solvent effects.  The method is implemented for
RHF, UHF, ROHF, GVB and MCSCF wavefunctions and gradients,
and so can be used with any RUNTYP involving the gradient.
The method is not implemented for MP2, CI, any of the
semiempirical models, or for analytic hessians.

DIELEC = the dielectric constant, 80 is often used for H2O

RADIUS = the spherical cavity radius, in Angstroms

G      = the proportionality constant relating the solute
         molecule's dipole to the strength of the reaction
         field.  Since G can be calculated from DIELEC and
         RADIUS, do not give G if they were given.

   Additional information on the $SCRF model can be found
in the References chapter of this manua.

==========================================================

$ECP group               (required if ECP=READ in $CONTRL)

    This group lets you read in effective core potentials,
for some or all of the atoms in the molecule.  You can
use built in potentials for some of the atoms if you like.
This is a free format (positional) input group.

*** Give a card set -1-, -2-, and -3- for each atom ***

-card 1-    PNAME, PTYPE, IZCORE, LMAX+1

PNAME is a 8 character descriptive tag for this potential.
      If it is repeated for a subsequent atom, no other
      information need be given on this card, and cards
      -2- and -3- may also be skipped.  The information
      will be copied from the first atom by this PNAME.
      Do not use the option to repeat the previously read
      ECP for an atom with PTYPE=NONE, instead type "none".
PTYPE = GEN    a general potential should be read.
      = SBKJC  look up the Stevens/Basch/Krauss/Jasien/
               Cundari potential for this type of atom.
      = HW     look up the Hay/Wadt built in potential
               for this type of atom.
      = NONE   treat all electrons on this atom.
IZCORE is the number of core electrons to be removed.
LMAX   is the maximum angular momentum occupied in the
       core orbitals being removed (usually).  Give
       IZCORE and LMAX only if PTYPE is GEN.

*** For the first occurence of PNAME, if PTYPE is GEN, ***
*** then give cards -2- and -3-.  Otherwise go to -1-. ***

*** Card sets -2- and -3- are repeated LMAX+1 times    ***

    The potential U(LMAX+1) is given first,
    followed by U(L)-U(LMAX+1), for L=1,LMAX.

-card 2-    NGPOT

NGPOT is the number of Gaussians in this part of the
      local effective potential.

-card 3-    CLP,NLP,ZLP   (repeat this card NGPOT times)

CLP is the coefficient of this Gaussian in the potential.
NLP is the power of r for this Gaussian.
ZLP is the exponent of this Gaussian.

                      * * *

By far the easiest way to use the SBKJC potential for all
atoms in the formic acid molecule is to request ECP=SBKJC
in $CONTRL.  But the next page shows two alternatives.
The first way is to look up the program's internally
stored SBKJC potentials one atom at a time:

 $ECP
C-ECP SBKJC
H-ECP NONE
O-ECP SBKJC
O-ECP
H-ECP NONE
 $END

The second oxygen duplicates the first, no core electrons
are removed for hydrogen.  The order of the atoms must
follow that generated by $DATA.  Note PTYPE allows you to
type in one or more atoms explicitly, while using built in
data for some other atoms.

The second example reads all SBKJC potentials explicitly:

 $ECP
C-ECP GEN 2 1
1      ----- CARBON U(P) -----
 -0.89371  1  8.56468
2      ----- CARBON U(S)-U(P) -----
  1.92926  0  2.81497
 14.88199  2  8.11296
H-ECP NONE
O-ECP GEN 2 1
1      ----- OXYGEN U(P) -----
 -0.92550  1 16.11718
2      ----- OXYGEN U(S)-U(P) -----
  1.96069  0  5.05348
 29.13442  2 15.95333
O-ECP
H-ECP NONE
 $END

Again, the 2nd oxygen copies from the first.  It is handy
to use the rest of card -2- as a descriptive comment.

As a final example, for antimony we have LMAX+1=3 (there
are core d's).  One must first enter U(f), followed by
U(s)-U(f), U(p)-U(f), U(d)-U(f).

Caution:
-------
At the present time, there are some numerical problems in
the ECP code, which has been programed to use spdfg basis
sets, and core potentials up to g.  If one is using a g
basis function, or a g potential (bottom row elements
beyond the lanthanide series), there are small errors in
the ECP integrals.  A tight optimization (OPTTOL=1D-05)
will usually result in the energy rising slightly during
the last few geometry steps.  The error seems to be about
0.000002 Hartree, so be cautious about using a g potential
or basis function.  When both are used in the same run,
the error in the energy is about 0.0002, which means the
use of both is too inaccurate to be trusted.  The use of
f functions or f potentials (or lower) seems to be free of
any errors.

==========================================================

$EFIELD group   (not required)

    This group permits the study of the influence of an
external electric field on the molecule.  The method is
general, and so works for all ab initio SCFTYPs.

EVEC        = an array of the three x,y,z components of
              the applied electric field.

SYM         = a flag to specify when the field to be
              applied breaks the molecular symmetry.
              Since most fields break symmetry, the
              default is .FALSE.

==========================================================

Restrictions: analytic hessians are not available, but
numerical hessians are.  Because an external field causes
a molecule with a dipole to experience a torque, geometry
optimizations must be done in Cartesian coordinates only.
Internal coordinates eliminate the rotational degrees of
freedom, which are no longer free.

Notes: a hessian calculation will have two rotational
modes with non-zero "frequency", caused by the torque.
A gas phase molecule will rotate so that the dipole
moment is anti-parallel to the applied field.  To carry
out this rotation during geometry optimization will take
many steps, and you can help save much time by inputting
a field opposite the molecular dipole.  There is also
a stationary point at higher energy with the dipole
parallel to the field, which will have two imaginary
frequencies in the hessian.  Careful, these will appear
as the first two modes in a hessian run, but will not
have the i for imaginary included on the printout since
they are rotational modes.

==========================================================

$INTGRL group                                   (optional)

    This group controls AO integral formats.  It should
probably never be given, as the program always picks
sensible values.

 SCHWRZ = a flag to activate use of the Schwarz inequality
          to predetermine small integrals.  There is no
          loss of accuracy when choosing this option, and
          there are appreciable time savings for bigger
          molecules.  Default=.TRUE. for over 5 atoms, or
          for direct SCF, and is .FALSE. otherwise.

 NOPK   = 0 PK integral option on, which is permissible
            for RHF, UHF, ROHF, GVB energy/gradient runs.
        = 1 PK option off (default for all jobs).
            Must be off for anything with a transformation.

 NORDER = 0 (default)
        = 1 Sort integrals into canonical order.  There
            is little point in selecting this option, as
            no part of GAMESS requires ordered integrals.
            See also NSQUAR.

 NINTMX =   Maximum no. of integrals in a record block.
            (default=15000 for J or P file, =10000 for PK)

      The following parameters control the integral sort.
      (values given are defaults)

 NSQUAR = 0 Sorted integrals will be in triangular
            canonical order (default)
        = 1 instead sort to square canonical order.
 NDAR   = Number of direct access logical records to be
          used for the integral sort (default=2000)
 LDAR   = Length of direct access records (site dependent)
 NBOXMX =  200   Maximum number of bins.
 NWORD  =    0   Memory to be used (default=all of it).
 NOMEM  =    0   If non-zero, force external sort.

      The following parameters control integral restarts
      (values given are defaults)
 IST=    1      JST=    1    KST=    1    LST=    1
 NREC=   1      INTLOC= 1

==========================================================

$TRANS group                (optional for -CI- or -MCSCF-)
                           (relevant to analytic hessians)
                         (relevant to energy localization)

     This group controls the integral tranformation.  MP2
integral transformations are controlled instead by the
$MP2 input group.  There is little reason to give any but
the first variable.

 DIRTRF = a flag to recompute AO integrals rather than
          storing them on disk.  The default is .FALSE.
          for MCSCF and CI runs.  If your job reads $SCF,
          and you select DIRSCF=.TRUE. in that group, a
          direct transformation will be done, no matter
          how DIRTRF is set.

    Note that the transformation may do many passes over
    the AO integrals for large basis sets, and thus the
    direct recomputation of AO integrals can be very time
    consuming.

 MPTRAN = method to use for the integral transformation.
          the default is try 0, then 1, then 2.
          0 means use the incore method
          1 means use the segmented method.  This is the
            only method that works in parallel.
          2 means use the alternate method, which uses
            less memory than 2, but requires an extra
            large disk file.

 NWORD  = Number of words of fast memory to allow.  Zero
          uses all available memory. (default=0)

 CUTTRF = Threshold cutoff for keeping transformed two
          electron integrals.  (default= 10**(-9))

 AOINTS = defines AO integral storage during conventional
          integral transformations, during parallel runs.
          DUP stores duplicated AO lists on each node, and
          is the default for parallel computers with slow
          interprocessor communication, e.g. ethernet.
          DIST distributes the AO integral file across
          all nodes, and it is the default for parallel
          computers with high speed communications.

==========================================================

The remaining groups apply only to -CI- and -MCSCF- runs.

          * * * * * * * * * * * * * * * * * * * *
          For hints on how to do -CI- and -MCSCF-
           see the 'further information' section
          * * * * * * * * * * * * * * * * * * * *

                                                    $CIINP

==========================================================

$CIINP group  (optional, relevant for CITYP=GUGA or ALDET)

    This group is the control box for Graphical Unitary
Group Approach (GUGA) CI calculations, or Ames Laboratory
determinant (ALDET) full CI.  Each step which is executed
potentially requires a further input group described later.

NRNFG = An array of 10 switches controlling which steps of
        a CI computation are performed.
        1 means execute the module, 0 means don't.

  NRNFG(1) = Generate the configurations.  See either
             $CIDRT or $CIDET input.  (default=1)
  NRNFG(2) = Transform the integrals. See $TRANS.
             (default=1)
  NRNFG(3) = Sort integrals and calculate the Hamiltonian
             matrix. See $CISORT and $GUGEM. (default=1)
             This does not apply to ALDET.
  NRNFG(4) = Diagonalize the Hamiltonian matrix.
             See $GUGDIA or $CIDET. (default=1)
  NRNFG(5) = Construct the one electron density matrix,
             and generate NO's. See $GUGDM or $CIDET.
             (default=1)
  NRNFG(6) = Construct the two electron density matrix.
             See $GUGDM2 or $CIDET.
             (default=0 normally, but 1 for CI gradients)
  NRNFG(7) = Construct the Lagrangian of the CI function.
             Requires DM2 matrix exists.  See $LAGRAN.
             (default=0 normally, but 1 for CI gradients)
             This does not apply to ALDET.
  NRNFG(8-10) are not used.

Users are not encouraged to change these values, as the
defaults are quite reasonable ones.

NPFLG = An array of 10 switches to produce debug printout.
        There is a one to one correspondance to NRNFG, set
        to 1 for output. (default = 0,0,0,0,0,0,0,0,0,0)
        The most interesting is NPFLG(2)=1 to see the
        transformed 1e- integrals, NPFLG(2)=2 adds the
        very numerous transformed 2e- integrals to this.

IREST = n    Restart the -CI- at stage NRNFG(n).
==========================================================

$DET group     (required for SCFTYP=MCSCF if CISTEP=ALDET)
$CIDET group                     (required if CITYP=ALDET)

   This group describes the determinants to be used in a
full MCSCF active space, or full CI wavefunction.

   Determinants contain several spin states, in contrast
to configuration state functions.  The Sz quantum number
of each determinant is the same, but the Hamiltonian
eigenvectors will have various spins S=Sz, Sz+1, Sz+2, ...
In addition, the determinant CI code does not exploit the
spatial symmetry of the orbitals, so the CI states will
include not only various spin symmetries, but also all
space symmetries.  You may need to think about NSTATE!

   There is no default for NCORE, NACT, and NELS:

NCORE  = total number of orbitals doubly occupied in all
         determinants.

NACT   = total number of active orbitals.

NELS   = total number of active electrons.

SZ     = azimuthal spin quantum number for each of the
         determinants, two times SZ is therefore the
         number of excess alpha spins in each determinant.
         The default is SZ=S, extracted from the MULT=2S+1
         given in $CONTRL.

 * * * the following control the diagonalization * * *

NSTATE = Number of CI states to be found, the default is
         1.  The maximum number of states is 100.

PRTTOL = Printout tolerance for CI coefficients, the
         default is to print any larger than 0.05.

ITERMX = Maximum number of Davidson iterations per root.
         The default is 100.

CVGTOL = Convergence criterion for Davidson eigenvector
         routine.  This value is proportional to the
         accuracy of the coeficients of the eigenvectors
         found.  The energy accuracy is proportional to
         its square.  The default is 1.0E-5.

NHGSS  = dimension of the Hamiltonian submatrix which
         is diagonalized to obtain the initial guess
         eigenvectors.  The determinants forming the
         submatrix are chosen on the basis of a low
         diagonal energy, or if needed to complete a
         spin eigenfunction.  The default is 300.

NSTGSS = Number of eigenvectors from the initial guess
         Hamiltonian to be included in the Davidson's
         iterative scheme.  It is seldom necessary to
         include extra states to obtain convergence to
         the desired states.  The default is the value
         for NSTATE.

MXXPAN = Maximum number of expansion basis vectors in the
         iterative subspace during the Davidson iterations
         before the expansion basis is truncated.  The
         default is the larger of 10 or NSTGSS+1.  If this
         value is decreased, convergence is hurt but the
         memory required is decreased.

* * * the following control the 1st order density * * *
These are ignored during MCSCF, but are used during a CI.

IROOT  = the root whose density is saved on the disk file
         for subsequent property analysis.  Only one root
         can be saved, and the default value of 1 means
         the ground state.  Be sure to set NFLGDM to form
         the density of the state you are interested in!

NFLGDM = Controls each state's density formation.
         0 -> do not form density for this state.
         1 -> form density and natural orbitals for this
              state, print and punch occ.nums. and NOs.
         2 -> same as 1, plus print density over MOs.
         The default is NFLGDM(1)=1,0,0,...,0 meaning
         only ground state NOs are generated.

    * * * the following control the state averaged
    * * * 1st and 2nd order density matrix computation
Usually ignored by CI runs, these are relevant to MCSCF.

PURES  = a flag controlling the spin purity of the state
         avaraging.  If true, the WSTATE array pertains
         to the lowest states of the same S value as is
         given by the MULT keyword in $CONTRL.  In this
         case the value of NSTATE will need to be bigger
         than the total number of weights given by WSTATE
         if there are other spin states present at low
         energies.  If false, it is possible to state
         average over more than one S value, which might
         be of interest in spin-orbit coupling jobs.
         The default is .TRUE.

WSTATE = An array of up to 100 weights to be given to the
         densities of each state in forming the average.
         The default is to optimize a pure ground state,
         WSTATE(1)=1.0,0.0,...,0.0
         A small amount of the ground state can help the
         convergence of excited states greatly.
         Gradient runs are possible only with pure states.
         Be sure to set NSTATE above appropriately!

==========================================================

$DRT group      (required for SCFTYP=MCSCF if CISTEP=GUGA)
$CIDRT group                      (required if CITYP=GUGA)

    This group describes the -MCSCF- or -CI- wavefunction.
The distinct row table is the means by which the Graphical
Unitary Group Approach (GUGA) names the configurations.

   The group is spelled DRT for MCSCF runs, and CIDRT for
CI runs.  The main difference in these is NMCC vs. NFZC.

    There is no default for GROUP, and you must choose one
of FORS, FOCI, SOCI, or IEXCIT.


GROUP = the name of the point group to be used.  This is
        usually the same as that in $DATA, except for
        RUNTYP=HESSIAN, when it must be C1.  Choose from
        the following: C1, C2, CI, CS, C2V, C2H, D2, D2H,
        C4V, D4, D4H.  If your $DATA group is not listed,
        choose only C1 here.

FORS  = flag specifying the Full Optimized Reaction Space
        set of configuration should be generated.  This
        is usually set true for MCSCF runs, but if it is
        not, see FORS in $MCSCF.  (Default=.FALSE.)

FOCI  = flag specifying first order CI.  In addition to
        the FORS configurations, all singly excited CSFs
        from the FORS reference are included.
        Default=.FALSE.

SOCI  = flag specifying second order CI.  In addition to
        the FORS configurations, all singly and doubly
        excited configurations from the FORS reference
        are included.  (Default=.FALSE.)

IEXCIT= electron excitation level, for example 2 will
        lead to a singles and doubles CI.  This variable
        is computed by the program if FORS, FOCI, or
        SOCI is chosen, otherwise it must be entered.

  * * the next variables define the single reference * *

    The single configuration reference is defined by
filling in the orbitals by each type, in the order shown.
The default for each type is 0.

       Core orbitals, which are always doubly occupied:
NMCC = number of MCSCF core MOs (in $DRT only).
NFZC = number of CI frozen core MOs (in $CIDRT only).

       Internal orbitals, which are partially occupied:
NDOC = number of doubly occupied MOs in the reference.
NAOS = number of alpha occupied MOs in the reference,
       which are singlet coupled with a corresponding
       number of NBOS orbitals.
NBOS = number of beta spin singly occupied MOs.
NALP = number of alpha spin singly occupied MOs in the
       reference, which are coupled high spin.
NVAL = number of empty MOs in the reference.

       External orbitals, occupied only in FOCI or SOCI:
NEXT = number of external MOs.  If given as -1, this will
       be set to all remaining orbitals (apart from any
       frozen virtual orbitals).
NFZV = number of frozen virtual MOs, never occupied.


       * * * the final choices are seldom used * * *

INTACT= flag to select the interacting space option.
        The CI will include only those spin couplings
        which have a nonvanishing matrix element with
        the reference configuration.

MXNINT = Buffer size for sorted integrals. (default=20000)

MXNEME = Buffer size for energy matrix.  (default=10000)

NPRT   = Configuration printout control switch.
         This can consume a HUMUNGUS amount of paper!
         0 = no print (default)
         1 = print electron occupancies, one per line.
         2 = print determinants in each CSF.

==========================================================

$MCSCF group                        (optional for -MCSCF-)

    This group controls the MCSCF orbital optimization
step.  The difference between the four convergence methods
is outlined in Chapter Four of this manual, which you must
carefully study before attempting MCSCF computations.

 --- the next choose the configuration basis ---

CISTEP = ALDET chooses the Ames Lab. determinant CI, and
               requires $DET input. (default)
       = GUGA  chooses the graphical unitary group CSFs,
               and requires $DRT input.  This is the
               only value usable with the QUAD converger.

 --- the next four choose the orbital optimizer ---

FOCAS  = a flag to select a method with a first order
         convergence rate.  (default=.FALSE.)

SOSCF  = a flag selecting an approximately second order
         convergence method.  (default=.TRUE.)

FULLNR = a flag selecting a second order method, with an
         exact orbital hessian.  (default=.FALSE.)

QUAD   = a flag to pick a fully quadratic (orbital and
         CI coefficient) optimization method, which is
         applicable to FORS or non-FORS wavefunctions.
         QUAD may not be used with state-averaging.
         (default = .FALSE.)

Note that FOCAS must be used only with FORS=.TRUE. in $DRT.
The other convergers are usable for either FORS or non-FORS
wavefunctions, although convergence is always harder in the
latter case, when FORS below must be set .FALSE.

   --- the next apply to all convergence methods ---

FORS   = a flag to specify that the MCSCF function is of
         the Full Optimized Reaction Space type, which is
         sometimes known as CAS-SCF.  .TRUE. means omit
         act-act rotations from the optimization.  Since
         convergence is usually better for FULLNR with
         these rotations included, the default is sensible
         for the case FORS=.TRUE. in $DRT.  (default is
         .TRUE. for FOCAS/SOSCF, .FALSE. for FULLNR/QUAD)

ACURCY = the major convergence criterion, the maximum
         permissible asymmetry in the Lagrangian matrix.
         (default=1.0E-05)

ENGTOL = a secondary convergence criterion, the run is
         considered converged when the energy change is
         smaller than this value. (default=1.0E-10)

MAXIT  = Maximum number of iterations (default=100 for
         FOCAS, 60 for SOSCF, 30 for FULLNR or QUAD)

MICIT  = Maximum number of microiterations within a
         single MCSCF iteration. (default=5 for FOCAS
         or SOSCF, or 1 for FULLNR or QUAD)

NWORD  = The maximum memory to be used, the default is
         to use all available memory.  (default=0)

CANONC = a flag to cause formation of the closed shell
         Fock operator, and generation of canonical core
         orbitals.  This will order the MCC core by their
         orbital energies.  (default=.TRUE.)

EKT    = a flag to cause generation of extended Koopmans'
         theorem orbitals and energies.  (Default=.FALSE.)
    For this option, see R.C.Morrison and G.Liu,
    J.Comput.Chem., 13, 1004-1010 (1992).  Note that
    the process generates non-orthogonal orbitals, as
    well as physically unrealistic energies for the
    weakly occupied MCSCF orbitals.  The method is
    meant to produce a good value for the first I.P.

NPUNCH = MCSCF punch option (analogous to $SCF NPUNCH)
         0  do not punch out the final orbitals
         1  punch out the occupied orbitals
         2  punch out occupied and virtual orbitals
             The default is NPUNCH = 2.

NPFLG  = an array of debug print control.  This is
         analagous to the same variable in $CIINP.
         Elements 1,2,3,4,6,8 make sense, the latter
         controls debugging the orbital optimization.

  --- the next refers to SOSCF optimizations ---

NOFO   = set to 1 to skip use of FOCAS for one iteration
         during SOSCF.  This is a testing parameter, at
         present NOFO defaults to 0 to do one FOCAS iter.

   --- the next three refer to FOCAS optimizations ---

CASDII = threshold to start DIIS (default=0.05)

CASHFT = level shift value (default=1.0)

NRMCAS = renormalization flag, 1 means do Fock matrix
         renormalization, 0 skips (default=1)

   --- the next applies to the QUAD method ---
    (note that FULLNR input is also relevant)

QUDTHR = threshold on the orbital rotation parameter,
         SQCDF, to switch from the initial FULLNR
         iterations to the fully quadratic method.
         (default = 0.05)

   --- all remaining input applies only to FULLNR ---

DAMP   = damping factor, this is adjusted by the program
         as necessary.  (default=0.0)

METHOD = DM2 selects a density driven construction of the
         Newton-Raphson matrices.  (default).
       = TEI selects 2e- integral driven NR construction.
         See the 'further information' section for more
         details concerning these methods.  TEI is slow!

LINSER = a flag to activate a method similar to direct
         minimization of SCF.  The method is used if
         the energy rises between iterations.  It may in
         some circumstances increase the chance of
         converging excited states.  (default=.FALSE.)

FCORE  = a flag to freeze optimization of the MCC core
         orbitals, which is useful in preparation for
         RUNTYP=TRANSITN jobs.  Setting this flag will
         automatically force CANONC false.  This option
         is incompatible with gradients, so can only be
         used with RUNTYP=ENERGY. (default=.FALSE.)

          --- the next four are seldom used ---

DROPC  = a flag to include MCC core orbitals during the
         CI computation.  The default is to drop them
         during the CI, instead forming Fock operators
         which are used to build the correct terms in
         the orbital hessian. (default = .TRUE.)

NORB   = the number of orbitals to be included in the
         optimization, the default is to optimize with
         respect to the entire basis.  This option is
         incompatible with gradients, so can only be used
         with RUNTYP=ENERGY.  (default=number of AOs
         given in $DATA).

MOFRZ  = an array of orbitals to be frozen out of the
         orbital optimization step (default=none frozen).

NOROT  = an array of up to 250 pairs of orbital rotations
         to be omitted from the NR optimization process.
         The program automatically deletes all core-core
         rotations, all act-act rotations if FORS=.T.,
         and all core-act and core-virt rotations if
         FCORE=.T.  Additional rotations are input as
         I1,J1,I2,J2... to exclude rotations between
         orbital I running from 1 to NORB, and J running
         up to the smaller of I or NVAL in $TRANS.

==========================================================

$MCQDPT group       (relevant to SCFTYP=MCSCF if MPLEVL=2)

     Controls 2nd order MCQDPT (multiconfiguration quasi-
degenerate perturbation theory) runs, if requested by
MPLEVL=2 in $CONTRL.  MCQDPT2 is implemented only for
FORS (aka CASSCF) wavefunctions.   The MCQDPT method is a
multistate, as well as multireference perturbation theory.
The implementation is a separate program, interfaced to
GAMESS, with its own procedures for determination of the
canonical MOs, CSF generation, integral transformation,
CI in the reference CAS, etc.  Therefore some of the input
in this group repeats data given elsewhere, particularly
the $DET/$DRT.  A more complete discussion may be found in
the 'Further Information' chapter.  Analytic gradients are
not available.

       *** MCSCF reference wavefunction ***

NEL    =   total number of electrons, including core.
           (default from $DATA and ICHARG in $CONTRL)
MULT   =   spin multiplicity (default from $CONTRL)
NMOACT =   Number of orbitals in FORS active space
           (default is the active space in $DET or $DRT)
NMOFZC =   number of frozen core orbitals, NOT correlated
           in the perturbation calculation.  (default is
           number of chemical cores)
NMODOC =   number of orbitals which are doubly occupied in
           every MCSCF configuration, that is, not active
           orbitals, which are to be included in the
           perturbation calculation.  (The default is all
           valence orbitals between the chemical core and
           the active space)
NMOFZV =   number of frozen virtuals, NOT occupied during
           the perturbation calculation.  The default is
           to use all virtuals in the MP2.  (default=0)
ISTSYM =   the state symmetry of the target state(s).
           This is given as an integer, note that only
           Abelian groups are supported in $DATA:
             ISTSYM= 1   2   3   4   5   6   7   8
                C1   A
                Ci   Ag  Au
                Cs   A'  A''
                C2   A   B
                C2v  A1  A2  B1  B2
                C2h  Ag  Bg  Au  Bu
                D2   A   B1  B2  B3
                D2h  Ag  B1g B2g B3g Au  B1u B2u B3u
           (The default is 1, the totally symmetric state)

       *** perturbation specification ***

KSTATE=    state is used (1) or not (0) in the MCQDPT2.
           Maximum of 20 elements, including zeros.
           For example, if you want the perturbation
           correction to the second and the fourth roots,
               KSTATE(1)=0,1,0,1
           (default=1,0,0,0,0,0,0,...)

       *** MO input and flow control ***

INORB  = 0 optimize the MCSCF wavefunction in this run.
       = 1 read the converged orbitals from a $VEC group,
           and skip immediately to the MCQDPT computation.
           A complete $VEC including virtuals must be given.
           (default=0)

       *** Canonical Fock orbitals ***

IFORB  = 1 determine the canonical Fock orbitals
       = 0 omit this step.  (default=1)
AVECOE =   weight of each CAS-CI state in computing the
           closed shell Fock matrix.
           (default is AVECOE(1)=1.0,1.0,1.0,...)

       *** Miscellaneous options ***

THRGEN =   threshold for one-, two-, and three-body
           density matrix elements in the perturbation
           calculation.  If you want to obtain energies,
           for instance, to 6 figures after point, choose
           THRGEN=1.0D-08 or 1.0D-09.  (default=1.0D-08)
THRENE =   threshold for the energy convergence in the
           Davidson's method CAS-CI.  (default=-1.0D+00)
THRCON =   threshold for the vector convergence in the
           Davidson's method CAS-CI.  (default=1.0D-06)
LPOUT =    print option, 0 gives normal printout, while
           <0 gives debug print (e.g. -1,-5,-10,-100)
           (default=0)

Finally, there are additional very specialized input
options, described in the source code routine MQREAD:

IROT, ISELCT, LENGTH, MAXCSF, MAXERI, MAXROW, MDI, MXBASE,
MXTRFR, NSOLUT, NSTOP, GENZRO, THRERI, THRWGT, MAINCS,
NSTATE, NSTCI


==========================================================

$CISORT group    (optional, relevant for -CI- and -MCSCF-)

     This group provides further control over the sorting
of the transformed integrals.

NDAR   = Number of direct access records.
         (default = 2000)

LDAR   = Length of direct access record (site dependent)

NBOXMX = Maximum number of boxes in the sort.
         (default = 200)

NWORD  = Number of words of fast memory to use in this
         step.  A value of 0 results in automatic use of
         all available memory.  (default = 0)

NOMEM  = 0 (set to one to force out of memory algorithm)

==========================================================

$GUGEM group      (optional, relevant for -CI- or -MCSCF-)

    This group provides further control over the
calculation of the energy (Hamiltonian) matrix.

CUTOFF = Cutoff criterion for the energy matrix.
         (default=1.0E-8)

NWORD  = not used.

==========================================================

$GUGDIA group     (optional, relevant for -CI- or -MCSCF-)

     This group provides control over the Davidson method
diagonalization step.

NSTATE = Number of CI states to be found. (default=1)
         You can solve for any number of states, but only
         100 can be saved for subsequent sections, such
         as state averaging.

PRTTOL = Printout tolerance for CI coefficients
         (default = 0.05)

MXXPAN = Maximum no. of expansion basis vectors used
         before the expansion basis is truncated.
         (default=30)

ITERMX = Maximum number of iterations (default=50)

CVGTOL = Convergence criterion for Davidson eigenvector
         routine.  This value is proportional to the
         accuracy of the coeficients of the eigenvector(s)
         found.  The energy accuracy is proportional to
         its square.  (default = 1.0E-5)

NWORD  = Number of words of fast memory to use in this
         step.  A value of zero results in the use of all
         available memory.  (default = 0)

MEMMAX = 1000*limgiv + limh where limgiv is the largest
         matrix diagonalized via Givens-Householder
         (default=50) and limh is the dimension of the
         largest Hamiltonian that may be memory resident
         (default=100)

NIMPRV = Maximum no. of eigenvectors to be improved every
         iteration. (default = nstate)

NSELCT = Determines initial guess to eigenvectors.
         = 0 ->  Unit vectors corresponding to the NSTATE
                 lowest diagonal elements and any diagonal
                 elements within SELTHR of them. (default)
         < 0 ->  First abs(NSELCT) unit vectors.
         > 0 ->  use NSELCT unit vectors corresponding to
                  the NSELCT lowest diagonal elements.

SELTHR = Guess selection threshold when NSELCT=0.
         (default=0.01)

NEXTRA = Number of extra expansion basis vectors to be
         included on the first iteration.  NEXTRA is
         decremented by one each iteration.  This may be
         useful in "capturing" vectors for higher states.
         (default=5)

KPRINT = Print flag bit vector used when
         NPFLG(4)=1 in the $CIINP group       (default=8)
         value  1 bit 0 print final eigenvalues
         value  2 bit 1 print final tolerances
         value  4 bit 2 print eigenvalues and tolerances
                        at each truncation
         value  8 bit 3 print eigenvalues every iteration
         value 16 bit 4 print tolerances every iteration

==========================================================

$GUGDM group                 (optional, relevant for -CI-)

     This group provides further control over formation of
the 1-particle density matrix.

 NFLGDM = Controls each state's density formation.
          0 -> do not form density for this state.
          1 -> form density and natural orbitals for this
               state, print and punch occ.nums. and NOs.
          2 -> same as 1, plus print density over MOs.
          (default=1,99*0, meaning G.S. NOs only)
          See also NSTATE in $GUGDIA.  Note that forming
          the 1-particle density for a state is negligible
          against the diagonalization time for that state.

 IROOT  = The -CI- root whose density matrix is saved on
          the direct access dictionary file for later
          computation of properties.  (default=1)

 IBLOCK = Density blocking switch. If nonzero, the off
          diagonal block of the density below row IBLOCK
          will be set to zero before the (approximate)
          natural orbitals are found.  One use for this is
          to keep the internal and external orbitals in a
          FOCI or SOCI calculation from mixing.
          (default=0)

 NWORD  = Number of words of fast memory to use in this
          step.  A value of zero uses all available memory
          (default=0).

==========================================================

$GUGDM2 group     (optional, relevant for -CI- or -MCSCF-)

     This group provides control over formation of the
2-particle density matrix.

WSTATE = An array of up to 100 weights to be given to the
         2 body density of each state in forming the DM2.
         The default is to optimize a pure ground state.
         (Default=1.0,99*0.0)
         A small amount of the ground state can help the
         convergence of excited states greatly.
         Gradient runs are possible only with pure states.

         Be sure to set NSTATE in $GUGDIA appropriately!

CUTOFF = Cutoff criterion for the 2nd-order density.
         (default = 1.0E-9)

NWORD  = Number of words of fast memory to use in sorting
         the DM2.  The default uses all available memory.
         (default=0).

NOMEM  = 0 uses in memory sort, if possible.
       = 1 forces out of memory sort.

NDAR   = Number of direct access records. (default=4000)

LDAR   = Length of direct access record (site dependent)

NBOXMX = Maximum no. of boxes in the sort. (default=200)

==========================================================

$LAGRAN group       (optional, relevant for -CI- gradient)

     This group provides further control over formation of
the CI Lagrangian, a quantity which is necessary for the
computation of CI gradients.

 NOMEM =   0 form in core, if possible
       =   1 forces out of core formation
 NWORD =   0 (0=use all available memory)
 NDAR  = 4000
 LDAR  = Length of each direct access record
         (default is NINTMX from $INTGRL)

==========================================================

$TRFDM2 group       (optional, relevant for -CI- gradient)

     This group provides further control over the back
transformation of the 2 body density to the AO basis.

 NOMEM =   0 transform and sort in core, if possible
       =   1 transform in core, sort out of core, if poss.
       =   2 transform out of core, sort out of core
 NWORD =   0 (0=use all available memory)
 CUTOFF= 1.0D-9, threshold for saving DM2 values
 NDAR  = 2000
 LDAR  = Length of each direct access record
         (default is system dependent)
 NBOXMX= 200

==========================================================

Usually neither of these two groups is given.  Since these
groups are normally used only for CI gradient runs, we
list here some of the restrictions on the CI gradients:

  a) SCFTYP=RHF, only
  b) no FZV orbitals in $CIDRT, all MOs must be used.
  c) the derivative integrals are computed in the 2nd
     derivative code, which is limited to spd basis sets.
  d) the code does not run in parallel.
  e) Use WSTATE in $GUGDM2 to specify the state whose
     gradient is to be found.  Use IROOT in $GUGDM to
     specify the state whose other properties will be
     found.  These must be the same state!
  f) excited states often have different symmetry than the
     ground state, so think about GROUP in $CIDRT.
  g) the gradient can probably be found for any CI for
     which you have sufficient disk to do the CI itself.
     Time is probably about 2/3 additional.

==========================================================

$TRANST group               (relevant for RUNTYP=TRANSITN)
(only for CITYP=GUGA)       (relevant for RUNTYP=SPINORBT)

    This group controls the evaluation of the radiative
transition moment, or spin orbit coupling.  The defaults
assume that there is one common set of orbitals, all of
which are occupied.  The program can use two separately
optimized MO sets, provided certain conditions are met.

NUMVEC = the number of different MO sets. This can be
         either 1 or 2. (default=1)

NUMCI  = the number of different CI calculations to do.
         This should equal NUMVEC for TRANSITN, and is
         usually 2 or greater for SPINORBT (1 if the
         multiplicities of the states are the same).
         (default=1)

NOCC   = the number of occupied orbitals.  The default is
         the number of AOs given in $DATA, which is not
         usually correct.

NFZC   = When NUMVEC=2, this is the number of identical
         core orbitals in the two vector sets, and most
         likely this is NFZC in the $CDIRT groups.
         When NUMVEC=1, and for RUNTYP=TRANSITN, NFZC
         should equal NOCC, whereas for RUNTYP=SPINORBT,
         it should equal the NFZC value in the $CIDRTs.
         The default is the number of AOs given in $DATA,
         again this is not very reasonable.

IROOTS = array containing the number of CI states for which
         the transition moments are to be found.  The
         default is 1 for each CI, which is probably not a
         correct choice for TRANSITN runs, but is quite
         reasonable for SPINORBT.

NSTATE = array of CI states to be found when diagonalising
         the CI Hamiltonian.  Of those, the first IROOTS(i)
         will be used to find transition moments.  NSTATE
         in $GUGDIA overrides NSTATE(i), if it is larger.

Reasonable values for TRANSITN runs where you want to know
the moments for the first 4 states are IROOTS(1)=4
NSTATE(1)=8 for the case of a common orbital set, or
IROOTS(1)=1,4 NSTATE(1)=8,8 for two sets of orbitals.

* * * the next seven pertain only to spin-orbit runs * * *

METHOD = ZEFF  regards the nuclear charge appearing in
               the one electron operator as a scaling
               parameter to compensate for omitting the
               two electron term altogether.  (default)
       = BREIT includes the full 1e- and 2e- operator.
               Only singlet and triplet states can be
               coupled.  If you ask for more than one
               triplet state (iroots(2)>1), then no
               Hso diagonalisation will be performed.
               This code is presently limited to a
               maximum of 10 orbitals (32 bit machines)
               or about 16 orbitals (64 bit machines)
               in the active space.

ZEFTYP   specifies what Zeff charges to use
       = 3-21G  selects a set obtained by 3-21G, but
                probably approriate for any all electron
                basis set
       = SBK    selects a set obtained for the SBKJC ECP
                basis set, specifically.

ZEFF   = an array of effective nuclear charges overriding
         the charges chosen in ZEFTYP.  This pertains only
         to METHOD=ZEFF SPINORBT runs.
         (default: true charges with any effective core
          potential protons removed if ECPs are used).

TMOMNT = flag to control spin-orbit transition moment
         calculation (default is .FALSE.) (only with ZEFF)

SAVDSK = flag to repeat the form factor calculation twice.
         This saves disk space if limited storage is
         available.  (default=.FALSE.) (only with BREIT)

ACTION   control of disk file DAFL30 reuse.
       = NORMAL calculate the form factors in this run.
       = SAVE   calculate, and store the form factors on
                disk for future runs with the same active
                space characteristics.
       = READ   read the form factors from disk from an
                earlier run which used SAVE.
         (default=NORMAL) (only with BREIT)

MS     = limit spin projection of the triplet state
         0 do matrix elements for ms=0 only
         1 do matrix elements for ms=1 only
        -2 do matrix elements for all ms (0,1 and -1)
        -3 do not calculate any matrix element
           (ie useful for saving form factors)
        (default=-2) (only BREIT)

* * * the remaining parameters are not so important * * *

PRTCMO = flag to control printout of the corresponding
         orbitals.  (default is .FALSE.)

TOLZ   = MO coefficient zero tolerance (as for $GUESS).
         (default=1.0E-8)

TOLE   = MO coefficient equating tolerance (as for
         $GUESS).  (default=1.0E-5)

PRTPRM = flag to provide detailed information about the
         composition of the spin-mixed states in terms of
         adiabatic states. (default is .FALSE.) (only ZEFF)

PRMTOL = threshold for Slater determinant output.
         (default is 0.0) (only ZEFF)

==========================================================

        * * * * * * * * * * * * * * * * * * * * *
        For information on TRANSITN and SPINORBT,
        see the 'further information' section.
        * * * * * * * * * * * * * * * * * * * * *

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