title: Intermolecular interaction between W(CO)6 and alkane molecules probed by ultrafast vibrational energy relaxation: anomalously strong interaction between W(CO)6 and decane.
abstract: The rate of vibrational energy relaxation (VER) is a valuable probe of microscopic intermolecular interaction. In the present article, the VER rate of the T(1u) CO stretch of W(CO)(6) is measured in binary solutions composed of an alkane (hexane, decane, tetradecane) and cyclohexane or CCl(4), with seven mixing volume ratios. The volume ratio dependence indicates that, among the three alkane-cyclohexane solutions, only decane shows an exceptionally strong contribution to the VER process. It is strongly suggested that decane forms a specific solute-solvent complex with W(CO)(6). The "V-shaped" dependence of the VER rate on the number of carbons in alkane solvents (Banno, M.; Sato, S.; Iwata, K.; Hamaguchi, H. Chem. Phys. Lett. 2005, 412, 464.) is explained by the solute-solvent complex model. There are no experimental results that suggest the formation of the specific solute-solvent complex in alkane-CCl(4) solutions.
authors.affiliation: Department of Chemistry, School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-0033, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Banno
authors.forename: Koichi
authors.initials: K
authors.lastname: Iwata
authors.forename: Hiro-o
authors.initials: HO
authors.lastname: Hamaguchi