title: Characterization of the dispersion interactions and an ab initio study of van der Waals potential energy parameters for coinage metal clusters.
abstract: Dispersion interactions and van der Waals C(6) coefficients are studied in small model systems involving copper, silver, and gold atoms. We investigate a novel method where the intermolecular dispersion interactions are characterized by interatomic C(6) coefficients that can be used to formulate the dispersion energy as a separate contribution to the total interaction energy at long distances. We obtain the C(6) coefficients from a least-squares fit to the interaction energy surface. Other significant effects to the long-range interaction energy such as multipole-multipole and induction energy are explicitly taken into account. The electronic structure calculations are performed at the coupled cluster level including single, double, and perturbative triple excitations (CCSD(T) level) with triple-ζ basis sets.
authors.affiliation: Laboratory of Physical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), FIN-00014 University of Helsinki, Finland.
authors.forename: Richard
authors.initials: R
authors.lastname: Hatz
authors.forename: Markus
authors.initials: M
authors.lastname: Korpinen
authors.forename: Vesa
authors.initials: V
authors.lastname: Hänninen
authors.forename: Lauri
authors.initials: L
authors.lastname: Halonen