title: Coupled-cluster calculations of vibrational Raman optical activity spectra.
abstract: We present the first calculations of Raman optical activity spectra at the coupled-cluster level of theory. Calculations are presented for (S)-methyloxirane and compared to recent experimental gas-phase measurements as well as the results obtained at the Hartree-Fock and density functional level of theory using the popular B3LYP functional. For the experimentally relevant frequency region of 400-1600 cm(-1), the Hartree-Fock, B3LYP and coupled-cluster spectra are very similar when the same force field is used, and the results also agree well with experiment. For high-frequency vibrational modes, differences in the ROA difference parameters are observed and are analyzed. The new coupled-cluster ROA code will allow for critical benchmarking of the accuracy of modern exchange-correlation functionals in the calculation of ROA spectra.
authors.affiliation: Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, USA. crawdad@vt.edu
authors.forename: T Daniel
authors.initials: TD
authors.lastname: Crawford
authors.forename: Kenneth
authors.initials: K
authors.lastname: Ruud