Keyword Reference

This is a quick list of keywords and defaults across all sections of ChronusQ. This is meant as a reference; for more details, see the specific input section pages.

Section	Keyword	Type	Description	Default	Required?
`QM`	`REFERENCE`	String	Type of reference wavefunction	N/A	Yes
`QM`	`JOB`	String	Type of calculation	N/A	Yes
`QM`	`X2CTYPE`	String	Type of X2C transformation	`FULL`	No
`MOLECULE`	`CHARGE`	Signed Integer	Overall molecular charge (in electrons)	N/A	Yes
`MOLECULE`	`MULT`	Unsigned Integer	Approximate spin multiplicity	0	No
`MOLECULE`	`GEOM`	Multiline String	Geometry specification from input file (in Angstroms)	N/A	Yes if `MOLECULE.READGEOM` is `INPUTFILE`
`MOLECULE`	`READGEOM`	String	Location of geometry specification (`INPUTFILE` or `FCHK`)	`INPUTFILE`	No
`BASIS`/`DFBASIS`	`BASIS`	String	Basis set keyword or path	N/A	Sometimes
`BASIS`/`DFBASIS`	`DEFINEBASIS`	Boolean	Whether or not to read the basis definition from the input file	N/A	Sometimes
`BASIS`/`DFBASIS`	`BASISDEF`	Multiline string	Definition of a basis in Gaussian94 format	N/A	Yes if `BASIS.DEFINEBASIS` is `TRUE`
`BASIS`/`DFBASIS`	`FORCECART`	Boolean	Whether to force Cartesian basis functions	`FALSE`	No
`BASIS`/`DFBASIS`	`BASISTYPE`	String	Gaussian ("GTO") or gauge including ("GIAO") basis functions	`GTO`	No
`INTS`	`ALG`	String	ERI contraction algorithm	`DIRECT`	No
`INTS`	`SCHWARTZ`	Double precision float	Criterion for ERI schwartz screening	`10^{-12}`	No
`INTS`	`RI`	String	Method for the resolution of identity approximation (RI)	`FALSE`	No
`INTS`	`CDRI_THRESHOLD`	Double precision float	Criterion for inclusion in Cholesky decomposition based RI	`10^{-4}`	No
`INTS`	`FINITE_NUCLEI`	String	Toggles use of Gaussian charge distribution instead of point charges to represent nuclei	`DEFAULT`	No
`DFTINTS`	`EPS`	Double precision float	Screening tolerance on the DFT grid	`10^{-12}`	No
`DFTINTS`	`NANG`	Integer	Number of angular points in DFT grid	`302`	No
`DFTINTS`	`NRAD`	Integer	Number of radial points in DFT grid	`100`	No
`DFTINTS`	`NMACRO`	Integer	Number of radial shells in each DFT batch	`4`	No
`SCF`	`GUESS`	String	Initial guess for reference wave function	`SAD`	No
`SCF`	`FIELD`	Multiline string	Static external field specification in which to perform optimization	None	No
`SCF`	`ALG`	String	Algorithm for SCF procedure	`CONVENTIONAL`	No
`SCF`	`ENETOL`	Double precision float	Convergence tolerance for the change in total energy	`10^{-10}`	No
`SCF`	`DENTOL`	Double precision float	Convergence tolerance for the root-mean-squared change in the one particle density matrix	`10^{-8}`	No
`SCF`	`MAXITER`	Integer	Maximum number of SCF iterations	`128`	No
`SCF`	`INCFOCK`	Boolean	Whether or not to perform an incremental Fock build throughout the SCF for improved screening	`TRUE` if ERI formation is `DIRECT`; `FALSE` otherwise	No
`SCF`	`NINCFOCK`	Integer	Number of SCF iterations after which to start the incremental Fock build	`20`	No
`SCF`	`EXTRAP`	Boolean	Whether to do extrapolation of Fock matrix with DIIS and damping	`TRUE`	No
`SCF`	`DIIS`	Boolean	Whether to use direct inversion of the iterative subspace extrapolation (CDIIS specifically)	`TRUE`	No
`SCF`	`NKEEP`	Integer	Number of previous iterations to track for DIIS	`10`	No
`SCF`	`DAMP`	Boolean	Whether to damp Fock matrix changes	`TRUE`	No
`SCF`	`DAMPPARAM`	Double precision float	Damping parameter	`0.7`	No
`SCF`	`DAMPERROR`	Double precision float	Energy difference after which to turn off Fock damping	`10^{-3}`	No
`SCF`	`PRINTMOS`	Boolean	Whether or not to print MO coefficients after SCF procedure	`FALSE`	No
`RT`	`TMAX`	Double precision float	Maximum time to which to propagate in A.U.	N/A	Yes
`RT`	`DELTAT`	Double precision float	Time between each propagation step in A.U.	N/A	Yes
`RT`	`INTALG`	String	Propagation algorithm	`MMUT`	No
`RT`	`FIELD`	Multiline string	Time-dependent fields during propagation	None	No
`RT`	`RESTARTSTEP`	String	Algorithm to use for MMUT restart step	`MAGNUS2`	No
`RT`	`IRSTRT`	String	Number of steps between MMUT restart steps	`50`	No
`RT`	`SAVESTEP`	Integer	Number of steps between saving to the binary file	`50`	No
`RT`	`RESTART`	Boolean	Whether or not to restart propagation from the binary file	`FALSE`	No
`RT`	`SCFFIELD`	Boolean	Whether or not to use the time independent field from the SCF calculation during the RT calculation	`TRUE`	No
`RESPONSE`	`TYPE`	String	The response job type	`RESIDUE`	No
`RESPONSE`	`PROPAGATOR`	String	The quantum propagator used in the response function	`PARTICLEHOLE`	No
`RESPONSE`	`DOFULL`	Boolean	Whether or not to do the "full" problem, i.e. with (Sca)LAPACK. Implies FULLMAT if true	`TRUE`	No
`RESPONSE`	`FULLMAT`	Boolean	Whether or not to build the full propagator in memory	`TRUE`	No
`RESPONSE`	`NROOTS`	Integer	Number of desired roots for a RESIDUE job (see RESP.TYPE keyword). Only used if `DOFULL=FALSE`	`3`	No
`RESPONSE`	`DEMIN`	Double precision float	Minimum energy for a RESIDUE job (see RESP.TYPE keyword). Only used if DOFULL=FALSE	`0.0`	No
`RESPONSE`	`MAXITER`	Integer	Maximum number of iterations for iterative response job	`500`	No
`RESPONSE`	`AOPS`	String	Output observable operators	`ALLOPS`	No
`RESPONSE`	`BOPS`	String	Input perturbation operators	`EDL`	No
`RESPONSE`	`BFREQ`	String	Frequencies for applied BOPs	`0.0`	No
`RESPONSE`	`DAMP`	Double precision float	Damping parameter for FDR jobs (see RESP.TYPE keyword)	`0.0`	No
`RESPONSE`	`CONV`	Double precision float	Residual convergence critera for iterative response job	`1e^{-7}`	No
`RESPONSE`	`GPLHR_M`	Integer	Internal GPLHR subspace expansion parameter	`3`	No
`RESPONSE`	`GPLHR_SIGMA`	Double precision float	Internal GPLHR energy shift parameter	`0.0`	No
`RESPONSE`	`DISTMATFROMROOT`	Boolean	Whether to form matrix on root, then distribute (MPI only)	`FALSE`	No
`RESPONSE`	`FORMMATDIST`	Boolean	Whether to form the matrix distributed (MPI only)	`FALSE`	No
`MISC`	`MEM`	String	Amount of memory per process	100 MB	No
`MISC`	`NSMP`	Integer	Number of shared memory threads per process	1	No