title: Symmetry-adapted perturbation theory utilizing density functional description of monomers for high-spin open-shell complexes.
abstract: We present an implementation of symmetry-adapted perturbation theory (SAPT) to interactions of high-spin open-shell monomers forming high-spin dimers. The monomer spin-orbitals used in the expressions for the electrostatic and exchange contributions to the interaction energy are obtained from density functional theory using a spin-restricted formulation of the open-shell Kohn-Sham (ROKS) method. The dispersion and induction energies are expressed through the density-density response functions predicted by the time-dependent ROKS theory. The method was applied to several systems: NH...He, CN...Ne, H2O...HO2, and NH...NH. It provides accuracy comparable to that of the best previously available methods such as the open-shell coupled-cluster method with single, double, and noniterative triple excitations, RCCSD(T), with a significantly reduced computational cost.
authors.affiliation: Faculty of Chemistry, Warsaw University, Pasteura 1, 02-093 Warsaw, Poland.
authors.forename: Piotr S
authors.initials: PS
authors.lastname: Zuchowski
authors.forename: Rafał
authors.initials: R
authors.lastname: Podeszwa
authors.forename: Robert
authors.initials: R
authors.lastname: Moszyński
authors.forename: Bogumił
authors.initials: B
authors.lastname: Jeziorski
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Szalewicz