The dispersion interaction between quantum mechanics and effective fragment potential molecules

TitleThe dispersion interaction between quantum mechanics and effective fragment potential molecules
Publication TypeJournal Article
Year of Publication2012
AuthorsSmith QA, Ruedenberg K, Gordon MS, Slipchenko LV
Journal TitleJournal of Chemical Physics
Volume136
Pages244107
Date Published06
Type of ArticleArticle
ISBN Number0021-9606
Accession NumberWOS:000305881100009
Keywordsatom-atom potentials, BASIS-SETS, BENCHMARK CALCULATIONS, BENZENE DIMER, damping, density-functional theory, energy, functions, intermolecular potentials, orbital methods, wave-functions
Abstract

A method for calculating the dispersion energy between molecules modeled with the general effective fragment potential (EFP2) method and those modeled using a full quantum mechanics (QM) method, e. g., Hartree-Fock (HF) or second-order perturbation theory, is presented. C-6 dispersion coefficients are calculated for pairs of orbitals using dynamic polarizabilities from the EFP2 portion, and dipole integrals and orbital energies from the QM portion of the system. Dividing by the sixth power of the distance between localized molecular orbital centroids yields the first term in the commonly employed London series expansion. A C-8 term is estimated from the C-6 term to achieve closer agreement with symmetry adapted perturbation theory values. Two damping functions for the dispersion energy are evaluated. By using terms that are already computed during an ordinary HF or EFP2 calculation, the new method enables accurate and extremely rapid evaluation of the dispersion interaction between EFP2 and QM molecules. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729535]

URL<Go to ISI>://WOS:000305881100009
DOI10.1063/1.4729535
Alternate JournalJ. Chem. Phys.