title: Argon physisorption as structural probe for endohedrally doped silicon clusters.
abstract: We report on an element-dependent critical size for argon physisorption at 80 K on transition-metal-doped silicon clusters. Argon does not attach to elemental silicon clusters but only to surface-located transition-metal atoms. Thus physisorption provides structural information. Specifically, the minimal cluster size for the formation of endohedral singly metal-doped silicon cages has been determined. The observed critical size for doubly doped silicon clusters indicates that larger caged molecules can be formed, eventually leading to the growth of metal-doped silicon nanorods.
authors.affiliation: Laboratory of Solid State Physics and Magnetism & INPAC-Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
authors.forename: Ewald
authors.initials: E
authors.lastname: Janssens
authors.forename: Philipp
authors.initials: P
authors.lastname: Gruene
authors.forename: Gerard
authors.initials: G
authors.lastname: Meijer
authors.forename: Ludger
authors.initials: L
authors.lastname: Wöste
authors.forename: Peter
authors.initials: P
authors.lastname: Lievens
authors.forename: André
authors.initials: A
authors.lastname: Fielicke