30.8 Options

Options for canonical and local versions:

DF_BASIS=basis

Select the basis for density fitting (see section 11 for details). basis can either refer to a set name defined in the basis block, or to a default MP2 fitting basis (e.g., DF_BASIS=VTZ generates the VTZ/MP2FIT basis). By default, the MP2FIT basis that corresponds to the orbital basis is used.

RI_BASIS=basis

Select the basis for the resolution of the identity (RI). This can refer to a default basis set or a set name defined in a basis block. In case of R12-methods, this should be chosen to be a large uncontracted AO basis (at least AVQZ). For F12 methods the Hartree-Fock JKFIT basis sets perform very well for the RI, despite having been optimized for other purposes. The basis type can be appended to the basis name after a slash, e.g.
RI_BASIS=AVQZ/ORBITAL
would use the uncontracted AVQZ orbital basis set, and
RI_BASIS=VQZ/JKFIT
would use the JKFIT set. For R12 methods, the default type is ORBITAL and UNCONTRACT, while for F12 methods it is JKFIT. Contraction/uncontraction can be forced appending (CONTRACT) or (UNCONTRACT) to the basis name, e.g.,
RI_BASIS=AVQZ(UNCONTRACT)/ORBITAL. If other options are given in parenthesis, these can be separated by commas, e.g.,
RI_BASIS=AVQZ(f/d,UNCONTRACT)/ORBITAL.
Alternative forms, which should work as well, are
RI_BASIS=AVQZ(f/d)(UNCONTRACT)/ORBITAL
or
RI_BASIS=AVQZ(f/d)/ORBITAL(UNCONTRACT).
Note that the CONTRACT/UNCONTRACT option cannot be used with basis set names previously defined in a basis block.

ANSATZ=ansatz

Select the explicitly correlated ansatz ansatz methods. See section 30.9 for the possibilities and further details.

GEM_BASIS

Basis set name for geminal expansion; atom labels are ignored. This can either be OPTFULL (full nonlinear fit of the geminal expansion), EVEN (even tempered fit), or refer to a set name defined in a previous BASIS block. Default is OPTFULL.

GEM_TYPE

Frozen geminal type: LINEAR or SLATER, default is SLATER.

GEM_NUMBER

Number of Gaussian geminal functions (default 6).

GEM_CENTRE

Centre of even tempered geminal exponents, if GEM_BASIS=EVEN (default 1.0).

GEM_RATIO

Ratio of even tempered geminal exponents, if GEM_BASIS=EVEN (default 3.0).

GEM_BETA

Exponent for Slater-type frozen geminal, or parameter for weight function in other frozen geminal models (default 1.0 $a_0^{-1}$).

GEM_OMEGA

Exponent for weighting function (default -1, which means a value derived from GEM_BETA).

GEM_MOM

Exponent for r in omega fitting (default 0).

GEM_M

Exponent for r in weighting function (default 0).

GEM_MAXIT

Max. number of iterations in geminal optimization (default 200).

GEM_PRINT

Print parameter for geminal optimization (default 0).

GEM_DEBUG

Debug option for geminal optimization (default 0).

GEM_ACC

Convergence threshold for geminal line search (default 0.001).

GEM_FAC

Scaling factor for exponents in geminal optimization (default 1.0).

GEM_METHOD

Geminal optimization method (augmented Hessian (AH) or Newton-Raphson (NR), default AH).

GEM_TRUST

Trust ratio in AH geminal optimization (default 0.4).

GEM_SHIFT

Hessian shift in AH geminal optimization (default 0).

GEM_NUMERICAL

Flags numerical integration in geminal optimization (default 0).

GEM_PLOT

Geminal plot file (default blank).

PRINT=ipri

Select output level:

ipri=0

Standard output

ipri=1

Standard output plus more detailed information about integral evaluations.

ipri=2

Debugging output

THRBINV

Threshold below which non-physical eigenvalues are projected from approximate B matrices

THRF12

Threshold for integral screening contribution.