title: Electronic excitation energies in solution at equation of motion CCSD level within a state specific polarizable continuum model approach.
abstract: We present a study of excitation energies in solution at the equation of motion coupled cluster singles and doubles (EOM-CCSD) level of theory. The solvent effect is introduced with a state specific polarizable continuum model (PCM), where the solute-solvent interaction is specific for the state of interest. Three definitions of the excited state one-particle density matrix (1PDM) are tested in order to gain information for the development of an integrated EOM-CCSD/PCM method. The calculations show the accuracy of this approach for the computation of such property in solution. Solvent shifts between nonpolar and polar solvents are in good agreement with experiment for the test cases. The completely unrelaxed 1PDM is shown to be a balanced choice between computational effort and accuracy for vertical excitation energies, whereas the response of the ground state CCSD amplitudes and of the molecular orbitals is important for other properties, as for instance the dipole moment.
authors.affiliation: Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06511, USA. marco@gaussian.com
authors.forename: Marco
authors.initials: M
authors.lastname: Caricato
authors.forename: Benedetta
authors.initials: B
authors.lastname: Mennucci
authors.forename: Giovanni
authors.initials: G
authors.lastname: Scalmani
authors.forename: Gary W
authors.initials: GW
authors.lastname: Trucks
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Frisch