title: The accuracy of dipole moments from spin-component scaled CC2 in ground and electronically excited states.
abstract: The accuracy of dipole moments calculated from wave function methods based on second-order perturbation theory is investigated in the ground and electronically excited states. Results from the approximate coupled-cluster singles-and-doubles model, CC2, Møller-Plesset perturbation theory, MP2, and the algebraic diagrammatic construction through second-order, ADC(2), are discussed together with the spin-component scaled and the scaled opposite-spin variants of these methods. The computed dipole moments show a very good correlation with data from high-resolution spectroscopy. Compared to the unscaled methods, the spin-component scaling increases the accuracy of the results and improves the robustness of the calculations. An accuracy about 0.2 to 0.1 D in the ground state and about 0.3 to 0.2 D in the electronically excited states can be achieved with these approaches.
authors.affiliation: COSMOlogic GmbH & Co. KG, Burscheider Strasse 515, D-51381 Leverkusen, Germany. hellweg@cosmologic.de
authors.forename: Arnim
authors.initials: A
authors.lastname: Hellweg
mesh_terms: D004583:Electrons; D011789:Quantum Theory; D013499:Surface Properties