title: Rhodium Oxide Cluster Ions Studied by Thermal Desorption Spectrometry.
abstract: Gas-phase rhodium oxide clusters, RhnOm(+), were investigated by measuring the rate constants of oxidation and thermal desorption spectrometry. RhnOm(+) was suggested to be categorized into different states as m/n ≤ 1, 1 < m/n ≤ 1.5, and 1.5 < m/n in terms of energy and kinetics. For m/n ≤ 1, the O atoms readily adsorbed on the cluster with a large binding energy until RhO was formed. Under the O2-rich environment, oxidation proceeded until Rh2O3 was formed with a moderate binding energy. In addition, O2 molecules attached weakly to the cluster, and Rh2O3 formed RhnOm(+) (1.5 < m/n). The energetics and geometries of Rh6Om(+) (m = 6-12) were obtained using density functional theory calculations and were found to be consistent with the experimental results.
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo , Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Mafuné
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo , Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Takenouchi
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo , Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Miyajima
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo , Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kudoh