title: Excitation and circular dichroism spectra of (-)-(3aS, 7aS)-2-chalcogena-trans-hydrindans(Ch = S, Se, Te): SAC and SAC-CI calculations.
abstract: The ground and several electronic excited states of (3aS,7aS)-2-chalcogena-trans-hydrindans were calculated by the symmetry adapted cluster (SAC) and SAC-configuration interaction (SAC-CI) methods. Theoretical electronic excitation spectra and natural circular dichroism (CD) spectra were obtained for these compounds, and the calculated spectra showed good agreement with the experimental ones reported by Laur (Proceedings of the Third International Symposium on Organic Selenium and Tellurium compounds, Metz, France, 1979, pp. 219-299). For all the chalcogen compounds, the first singlet excited states are assigned to n-sigma* and the other states are assigned to n-Rydberg in our calculations. It indicates that the spectra for the sulfide, selenide, and telluride are almost regarded as the analogues except for the red shifts of the band positions from the sulfide to the telluride. For the telluride, however, the experimental spectra have shapes that cannot be interpreted by the singlet excitations solely. Our calculations predict the triplet states that account for the spectral shapes, indicating importance of the spin-orbit interaction effects for the accurate reproduction of the experimental spectra of the telluride.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Honda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kurihara
authors.forename: Masahiko
authors.initials: M
authors.lastname: Hada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakatsuji
mesh_terms: D018011:Chalcogens / Q000737:chemistry*; D002942:Circular Dichroism; D007192:Indenes / Q000737:chemistry*; D008968:Molecular Conformation; D013053:Spectrophotometry; D013237:Stereoisomerism; D013457:Sulfur Compounds / Q000737:chemistry*; D013691:Tellurium / Q000737:chemistry*
chemical_list: D018011:Chalcogens; D007192:Indenes; D013457:Sulfur Compounds; C488231:hydrindacene; D013691:Tellurium