Skip to content

Integrals

Keywords of the Integrals input block

Keyword Format Description Default
AutoauxThresh1 bool First threshold for generating the uncontracted automatic basis sets using Cholesky decomposition. Based on https://doi.org/10.1021/acs.jctc.1c00607 1e-7
AutoauxThresh2 bool Second threshold for contracting the uncontracted auxiliary basis sets using eigenvalue decomposition. Based on https://doi.org/10.1021/acs.jctc.3c00670 1e-5
DoRISOMF  bool Utilize the RI approximation during the computation of SOMF Coulomb integrals and the one-center approximation for SOMF exchange integrals.4,5 false
GridPointThresh double Determines the weight threshold for grid points to be discarded. 1e-12
SchwarzThresh double Threshold for screening the two-electron integrals using the Cauchy-Schwarz inequality. 1e-12
LebedevRule integer Determines the rule for the Lebedev angular grid. 11
OverlapFit bool If set to true invokes the overlap fitting procedure to optimize numerical integration to reproduce the overlap. true
RadialGridTol double Determines the radial error tolerance for the numerical integration grid. 3e-5
UseApproximateFock  bool If set to true invokes the RI approximation for the Coulomb part of the Fockian while the exchange part is calculated by seminumeric integration. false

  1. O. Vahtras, J. Almlöf, M. W. Feyereisen, Chem. Phys. Lett. 1993, 213, 514–518. ↩

  2. B. I. Dunlap, J. W. D. Connolly, J. R. Sabin, J. Chem. Phys. 1979, 71, 3396–3402. ↩

  3. R. Izsák, F. Neese, J. Chem. Phys. 2011, 135, 144105. ↩

  4. B. A. Hess, C. M. Marian, U. Wahlgren, O. Gropen, Chem. Phys. Lett. 1996, 251, 365–371. ↩

  5. F. Neese, J. Chem. Phys. 2005, 122, 034107. ↩