title: Coordination structures of the silver ion: infrared photodissociation spectroscopy of Ag(+)(NH(3))(n) (n = 3-8).
abstract: Infrared (IR) spectra are measured for Ag(+)(NH(3))(n) with n = 3-8 in the NH-stretch region using photodissociation spectroscopy. The spectra of n = 3 and 4 exhibit absorption features only near the frequencies of the isolated NH(3), indicating that every NH(3) molecule is coordinated individually to Ag(+). For n >or= 5, the occupation of the second shell is evidenced by lower-frequency features characteristic of hydrogen bonding between NH(3) molecules. Density functional theory and MP2 calculations are carried out in support of the experiments. A detailed comparison of the experimental and theoretical IR spectra reveals the preference for a tetrahedral coordination in the n = 5 and 6 ions. Likewise, most of the features observed in the spectra of n = 7 and 8 can be assigned to isomers containing a tetrahedrally coordinated inner shell as the basic structural motif. These results signify that the ammonia-solvated Ag(+) ion has a propensity toward a coordination number of four and the resulting tetrahedral Ag(+)(NH(3))(4) complex forms the central core of further solvation process.
authors.affiliation: Department of Molecular Chemistry, Graduate School of Sciences, Kyushu University, Hakozaki, Fukuoka, 812-8581, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Inoue
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ohashi
authors.forename: Takuro
authors.initials: T
authors.lastname: Iino
authors.forename: Jun
authors.initials: J
authors.lastname: Sasaki
authors.forename: Ken
authors.initials: K
authors.lastname: Judai
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Nishi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sekiya