mpqcsimp(3)

NAME
mpqcsimp - Simple Input
 The simple input format consists of keywords followed by a ':' followed by a value. The keywords are case sensitive. The values might be modified by options found in parenthesis. For example, the following input performs an optimization of water using density functional theory with the B3LYP exchange-correlation functional:

% B3LYP optimization of water
optimize: yes
method: KS (xc = B3LYP)
basis: 3-21G*
molecule:
    O    0.172   0.000   0.000
    H    0.745   0.000   0.754
    H    0.745   0.000  -0.754

Comments begin with a % and continue to the end of the line. Basis set names containing special characters, such as a space or parentheses, must be quoted inside a pair of double quotes. The accepted keywords are:

molecule
     Gives the atoms types and coordinates. The following options can be used

bohr
     The coordinates are given in Bohr.

angstrom
     The coordinates are given in Angstroms.

charge
     This option can be given after an 'element x y z' quadruple. This will override the charge on the atom. For example, (charge = 0) can be given for the ghost atoms in a counterpoise correction calculation.

multiplicity
     Gives the multiplicity of the molecule. The default is 1.

optimize
     If yes, then an optimization will be performed. The default is no. The following options can be given.

cartesian
     Use Cartesian coordinates.

internal
     Use internal coordinates.

redundant
     Use redundant internal coordinates.

gradient
     If yes, then a gradient calculation will be performed. The default is no.

frequencies
     If yes, then the frequencies will be obtained. The default is no.

charge
     Specificies the charge on the molecule. The default is 0.

method
     Specifices the method. There is no default and the possible values are:

HF
     Hartree-Fock. Unrestricted HF is used if multiplicity > 1

RHF
     Restricted Hartree-Fock.

UHF
     Unrestricted Hartree-Fock.

KS
     Kohn-Sham. Unrestricted KS is used if multiplicity > 1

RKS
     Restricted Kohn-Sham.

UKS
     Unrestricted Kohn-Sham.

MP2
     Second order Moeller-Plesset perturbation theory. Only available for multiplicity = 1.

MP2-R12/A
     The A version of MP2-R12. Only available for multiplicity = 1. An auxiliary basis should be specified. No gradient, optimization, or frequencies are possible.

MP2-R12/A'
     The A' version of MP2-R12. Only available for multiplicity = 1. An auxiliary basis should be specified. No gradient, optimization, or frequencies are possible.

ZAPT2
     Z-averaged perturbation theory. Only available for multiplicity > 1. No gradient, optimization, or frequencies are possible.

The following options are valid with the KS, RKS, and UKS methods:

grid
     Specifies the grid to be used for numerical integrations. The following values can be given:

xcoarse

coarse

medium

fine

xfine

ultrafine

xc
     Specifies the exchange-correlation functional. There is no default. See the table in the StdDenFunctional class documentation for the possible values.

basis
     Specifies the basis set. There is no default. See the table in the GaussianBasisSet class documentation for the available basis sets.

auxbasis
     Specifies the auxiliary basis set for MP2-R12 methods. There is no default. See the table in the GaussianBasisSet class documentation for the available basis sets.

restart
     Set to yes to restart an optimization. The default is no.

checkpoint
     Set to no to not save checkpoint files during an optimization. The default is yes.

symmetry
     Specifices the Schoenflies symbol of the point group of the molecule. The default is auto, which will cause to program to find the highest order Abelian subgroup of the molecule.

docc
     Gives the number of doubly occupied orbitals in each each irreducible representation in a parenthesized list. The symmetry must be specified and not be auto. The method must be restricted.

socc
     Gives the number of single occupied orbitals in each each irreducible representation in a parenthesized list. The symmetry must be specified and not be auto. The method must be restricted.

alpha
     Gives the number of alpha occupied orbitals in each each irreducible representation in a parenthesized list. The symmetry must be specified and not be auto. The method must be unrestricted.

beta
     Gives the number of beta occupied orbitals in each each irreducible representation in a parenthesized list. The symmetry must be specified and not be auto. The method must be unrestricted.

frozen_docc
     Gives the number of frozen core orbitals. Can be either a single integer or a parenthesized list giving the frozen core orbitals in each irreducible representation. In the latter case the symmetry must be given and not be auto.

frozen_uocc
     Gives the number of frozen virtual orbitals. Can be either a single integer or a parenthesized list giving the frozen virtual orbitals in each irreducible representation. In the latter case the symmetry must be given and not be auto.

memory
     Gives a hint for the amount of memory in bytes that can be used. This is typically a lower bound, more memory will be used in practice and the exact amount cannot be precisely controlled. The format is a fixed or floating point number optionally followed (without spaces) by one of the following suffixes: KB, MB, GB, KIB, MIB, or GIB.