Explicitly correlated coupled cluster methods with pair-specific geminals

Hans-Joachim Werner*, Gerald Knizia, Frederick R. Manby

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

151 Citations (Scopus)

Abstract

Explicitly correlated MP2-F12 and CCSD(T)-F12 methods with orbital-pair-specific Slater-type geminals are proposed. The fixed amplitude ansatz of Ten-no is used, and different exponents of the Slater geminal functions can be chosen for core-core, core-valence, and valence-valence pairs. This takes care of the different sizes of the correlation hole and leads to improved results when inner-shell orbitals are correlated. The complications and the extra computational cost as compared to corresponding calculations with a single geminal are minor. The improved accuracy of the method is demonstrated for spectroscopic properties of Br(2), As(2), Ga(2), Cu(2), GaCl, CuCl, and CuBr, where the d-orbitals are treated as core.

Original languageEnglish
Pages (from-to)407-417
Number of pages11
JournalMolecular Physics
Volume109
Issue number3
DOIs
Publication statusPublished - 2011

Keywords

  • 2ND-ORDER PERTURBATION-THEORY
  • ATOMS
  • AUXILIARY BASIS-SETS
  • MAIN-GROUP ELEMENTS
  • coupled-cluster
  • MOLECULAR INTEGRALS
  • FORMULATION
  • explicit correlation
  • CONVERGENT BASIS-SETS
  • CARTESIAN GAUSSIAN FUNCTIONS
  • PSEUDOPOTENTIALS
  • CONSISTENT BASIS-SETS
  • core-valence correlation
  • F12-methods

Cite this