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$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.

= 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.

Any SCFTYP except UHF may be followed

by a CI computation.

= 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.

$CONTRL

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.

* * * * * * * * * * * * * * * * * * * * * * * * *

$CONTRL

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).

* * * * * * *

$CONTRL

* * * 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!

$CONTRL

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. Contact Prof. Aage Hansen

in Copenhagen (nahaeh@vm.uni-c.dk) about this

program. (default is .FALSE.)

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.

$CONTRL

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