GLOBALS

General

ACTIVE

An array giving the number of active orbitals (occupied plus unoccupied) per irrep (shorthand to make MCSCF easier to specify than using RAS keywords)

  • Type: array

  • Default: No Default

BASIS_RELATIVISTIC

Auxiliary basis set for solving Dirac equation in X2C and DKH calculations. Defaults to decontracted orbital basis.

  • Type: string

  • Default: No Default

BENCH

Some codes (DFT) can dump benchmarking data to separate output files

  • Type: integer

  • Default: 0

BRIANQC_ENABLE

Whether to enable using the BrianQC GPU module

CC_TYPE

Algorithm to use for CC or CEPA computation (e.g., CCD, CCSD(T), CEPA(3), ACPF, REMP). See Cross-module Redundancies for details.

  • Type: string

  • Possible Values: DF, CONV, CD

  • Default: CONV

CI_TYPE

Algorithm to use for CI computation (e.g., CID or CISD). See Cross-module Redundancies for details.

  • Type: string

  • Possible Values: CONV

  • Default: CONV

CUBEPROP_BASIS_FUNCTIONS

List of basis function indices for which cube files are generated (1-based). All basis functions computed if empty.

  • Type: array

  • Default: No Default

CUBEPROP_FILEPATH

Directory to which to write cube files. Default is the input file directory.

  • Type: string

  • Default: No Default

CUBEPROP_ISOCONTOUR_THRESHOLD

Fraction of density captured by adaptive isocontour values

  • Type: double

  • Default: 0.85

CUBEPROP_ORBITALS

List of orbital indices for which cube files are generated (1-based, \(+\) for alpha, \(-\) for beta). All orbitals computed if empty.

  • Type: array

  • Default: No Default

CUBEPROP_TASKS

Properties to compute. Valid tasks include: DENSITY - Da, Db, Dt, Ds; ESP - Dt, ESP; ORBITALS - Psi_a_N, Psi_b_N; BASIS_FUNCTIONS - Phi_N; LOL - LOLa, LOLb; ELF - ELFa, ELFb; FRONTIER_ORBITALS - Psi_a_N_HOMO + Psi_a_N_LUMO; DUAL_DESCRIPTOR - DUAL_N_HOMO-M_LUMO.

  • Type: array

  • Default: No Default

CUBIC_GRID_OVERAGE

CubicScalarGrid spatial extent in bohr [O_X, O_Y, O_Z]. Defaults to 4.0 bohr each.

  • Type: array

  • Default: No Default

CUBIC_GRID_SPACING

CubicScalarGrid grid spacing in bohr [D_X, D_Y, D_Z]. Defaults to 0.2 bohr each.

  • Type: array

  • Default: No Default

DDX

DDX boolean for ddx module

DF_BASIS_CC

The density fitting basis to use in coupled cluster computations.

  • Type: string

  • Possible Values: basis string

  • Default: No Default

DOCC

An array containing the number of doubly-occupied orbitals per irrep (in Cotton order)

  • Type: array

  • Default: No Default

FREEZE_CORE

Specifies how many core orbitals to freeze in correlated computations. TRUE or 1 will default to freezing the previous noble gas shell on each atom. In case of positive charges on fragments, an additional shell may be unfrozen, to ensure there are valence electrons in each fragment. With FALSE or 0, no electrons are frozen (with the exception of electrons treated by an ECP). With -1, -2, and -3, the user might request strict freezing of the previous first/second/third noble gas shell on every atom. In this case, when there are no valence electrons, the code raises an exception. More precise control over the number of frozen orbitals can be attained by using the keywords NUM_FROZEN_DOCC (gives the total number of orbitals to freeze, program picks the lowest-energy orbitals) or FROZEN_DOCC (gives the number of orbitals to freeze per irreducible representation) or by the option POLICY in combination with appropriate inputs to FREEZE_CORE_POLICY At present, POLICY is an experimental option and is subject to change.

  • Type: string

  • Possible Values: FALSE, TRUE, 1, 0, -1, -2, -3, POLICY

  • Default: FALSE

FREEZE_CORE_POLICY

NOTE: This is an experimental feature and subject to change! Specifies a custom frozen-core policy on a per-element basis. Input should be a list of integers representing the number of orbitals to freeze for each atomic number MINUS one (so H is 0, He is 1, etc). For example, to specify that elements H-Be should have 0 frozen orbitals, B-Mg should have 1, and Al should have 2, you would provide the input [0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2]. Please make sure to fill in the list up to the highest atomic number included in any calculations. This option is only used if FREEZE_CORE is set to POLICY.

  • Type: array

  • Default: No Default

FROZEN_DOCC

An array containing the number of frozen doubly-occupied orbitals per irrep (these are not excited in a correlated wavefunction, nor can they be optimized in MCSCF. This trumps NUM_FROZEN_DOCC and FREEZE_CORE

  • Type: array

  • Default: No Default

FROZEN_UOCC

An array containing the number of frozen unoccupied orbitals per irrep (these are not populated in a correlated wavefunction, nor can they be optimized in MCSCF. This trumps NUM_FROZEN_UOCC

  • Type: array

  • Default: No Default

INTEGRAL_PACKAGE

Integral package to use. If compiled with Simint support, change this option to use them; LibInt2 is used otherwise.

  • Type: string

  • Possible Values: LIBINT2, SIMINT

  • Default: LIBINT2

LITERAL_CFOUR

Text to be passed directly into CFOUR input files. May contain molecule, options, percent blocks, etc. Access through cfour {...} block.

  • Type: string

  • Default: No Default

MAX_RADIAL_MOMENT

Maximum Radial Moment to Calculate

  • Type: integer

  • Default: 4

MBIS_D_CONVERGENCE

MBIS Convergence Criteria

MBIS_MAXITER

Maximum Number of MBIS Iterations

  • Type: integer

  • Default: 500

MBIS_PRUNING_SCHEME

Pruning scheme for MBIS Grid

  • Type: string

  • Default: ROBUST

MBIS_RADIAL_POINTS

MBIS Number of Radial Points

  • Type: integer

  • Default: 75

MBIS_SPHERICAL_POINTS

MBIS Number of Spherical Points

  • Type: integer

  • Default: 302

MOLDEN_WITH_VIRTUAL

Write all the MOs to the MOLDEN file (true) or discard the unoccupied MOs (false).

MP2_TYPE

Algorithm to use for MP2 computation. See Cross-module Redundancies for details.

  • Type: string

  • Possible Values: DF, CONV, CD

  • Default: DF

MP_TYPE

Algorithm to use for MPn ( \(n>2\) ) computation (e.g., MP3 or MP2.5 or MP4(SDQ)). See Cross-module Redundancies for details. Since v1.4, default for non-orbital-optimized MP2.5 and MP3 is DF.

  • Type: string

  • Possible Values: DF, CONV, CD

  • Default: CONV

NUM_FROZEN_DOCC

The number of core orbitals to freeze in later correlated computations. This trumps FREEZE_CORE

  • Type: integer

  • Default: 0

NUM_FROZEN_UOCC

The number of virtual orbitals to freeze in later correlated computations.

  • Type: integer

  • Default: 0

PCM

PCM boolean for pcmsolver module

PE

PE boolean for polarizable embedding module

PRINT

The amount of information to print to the output file. 1 prints basic information, and higher levels print more information. A value of 5 will print very large amounts of debugging information.

  • Type: integer

  • Default: 1

PROPERTIES

List of properties to compute

  • Type: array

  • Default: No Default

PROPERTIES_ORIGIN

Either a set of 3 coordinates or a string describing the origin about which one-electron properties are computed.

  • Type: array

  • Default: No Default

PUREAM

Do use pure angular momentum basis functions? If not explicitly set, the default comes from the basis set. Cfour Interface: Keyword translates into CFOUR_SPHERICAL

QC_MODULE

When several modules can compute the same methods and the default routing is not suitable, this targets a module. CCENERGY covers CCHBAR, etc. OCC covers OCC and DFOCC.

  • Type: string

  • Possible Values: CCENERGY, DETCI, DFMP2, FNOCC, OCC, CCT3, BUILTIN, MRCC

  • Default: No Default

RESTRICTED_DOCC

An array giving the number of restricted doubly-occupied orbitals per irrep (not excited in CI wavefunctions, but orbitals can be optimized in MCSCF)

  • Type: array

  • Default: No Default

RESTRICTED_UOCC

An array giving the number of restricted unoccupied orbitals per irrep (not occupied in CI wavefunctions, but orbitals can be optimized in MCSCF)

  • Type: array

  • Default: No Default

SCF_TYPE

What algorithm to use for the SCF computation. See Table SCF Convergence & Algorithm for default algorithm for different calculation types.

  • Type: string

  • Possible Values: DIRECT, DF, MEM_DF, DISK_DF, PK, OUT_OF_CORE, CD, GTFOCK, DFDIRJ, DFDIRJ+COSX, DFDIRJ+LINK

  • Default: PK

SCREENING

The type of screening used when computing two-electron integrals.

  • Type: string

  • Possible Values: SCHWARZ, CSAM, DENSITY, NONE

  • Default: CSAM

SOCC

An array containing the number of singly-occupied orbitals per irrep (in Cotton order). The value of DOCC should also be set.

  • Type: array

  • Default: No Default

WRITER_FILE_LABEL

Base filename for text files written by PSI, such as the MOLDEN output file, the Hessian file, the internal coordinate file, etc. Use the add_str_i function to make this string case sensitive.

  • Type: string

  • Default: No Default

Expert

CUBIC_BASIS_TOLERANCE

CubicScalarGrid basis cutoff.

CUBIC_BLOCK_MAX_POINTS

CubicScalarGrid maximum number of grid points per evaluation block.

  • Type: integer

  • Default: 1000

DEBUG

The amount of information to print to the output file

  • Type: integer

  • Default: 0

DERTYPE

Derivative level

  • Type: string

  • Possible Values: NONE, FIRST, SECOND, RESPONSE

  • Default: NONE

DIE_IF_NOT_CONVERGED

Psi4 dies if energy does not converge.

DKH_ORDER

Order of Douglas-Kroll-Hess

  • Type: integer

  • Default: 2

EXTERNAL_POTENTIAL_SYMMETRY

Assume external fields are arranged so that they have symmetry. It is up to the user to know what to do here. The code does NOT help you out in any way!

MAT_NUM_COLUMN_PRINT

Number of columns to print in calls to Matrix::print_mat.

  • Type: integer

  • Default: 5

PARENT_SYMMETRY

For displacements, symmetry (Schoenflies symbol) of ‘parent’ (undisplaced) reference molecule. Internal use only for finite difference.

  • Type: string

  • Default: No Default

RAS1

An array giving the number of orbitals per irrep for RAS1

  • Type: array

  • Default: No Default

RAS2

An array giving the number of orbitals per irrep for RAS2

  • Type: array

  • Default: No Default

RAS3

An array giving the number of orbitals per irrep for RAS3

  • Type: array

  • Default: No Default

RAS4

An array giving the number of orbitals per irrep for RAS4

  • Type: array

  • Default: No Default

RELATIVISTIC

Relativistic Hamiltonian type

  • Type: string

  • Possible Values: NO, X2C

  • Default: NO

WFN

Wavefunction type

  • Type: string

  • Default: SCF