title: Infrared photodissociation spectroscopy and density-functional calculations of protonated methanol cluster ions: Solvation structures of an excess proton.
abstract: Solvation structures of an excess proton in protonated methanol cluster ions, H(+)(CH(3)OH)(n) (n=5-8), were investigated by photodissociation spectroscopy in the middle infrared region (900-2300 cm(-1)) and by using density-functional theory. This work indicates that the excess proton is delocalized between two methanol molecules. Spectral features observed in the range 1400-1800 cm(-1) are attributed to vibrational modes involving collective motion of the shared proton and the two ligand molecules. At n=6-8, broad spectral features in the region above 1800 cm(-1) suggest coexistence of isomers in which the excess proton and a methanol molecule are tightly bound to form an ion core, CH(3)OH(2) (+).
authors.affiliation: Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan. tono@rs.kagu.tus.ac.jp
authors.forename: Kensuke
authors.initials: K
authors.lastname: Tono
authors.forename: Jer-Lai
authors.initials: JL
authors.lastname: Kuo
authors.forename: Masanori
authors.initials: M
authors.lastname: Tada
authors.forename: Koudai
authors.initials: K
authors.lastname: Fukazawa
authors.forename: Naoya
authors.initials: N
authors.lastname: Fukushima
authors.forename: Chiharu
authors.initials: C
authors.lastname: Kasai
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsukiyama