title: X-ray magnetic circular dichroism of size-selected, thiolated gold clusters.
abstract: We report herein the X-ray magnetic circular dichroism (XMCD) at the Au L2,3 edges of a series of Au clusters protected by glutathione (GSH). The samples used here included AuN(SG)M with (N, M) = (10, 10), (15, 13), (18, 14), (22, 16), (25, 18), (29, 20), (39, 24) and a sodium gold(I) thiomalate (SGT) as a reference. Magnetic moments per cluster were found to be increased with size, whereas those per Au-S bond were nearly constant. This finding suggests that a localized hole created by Au-S bonding at the gold/glutathione interface, rather than the quantum size effect, is responsible for the spin polarization of gold clusters.
authors.affiliation: Research Center for Molecular-Scale Nanoscience, Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Negishi
authors.forename: Hironori
authors.initials: H
authors.lastname: Tsunoyama
authors.forename: Motohiro
authors.initials: M
authors.lastname: Suzuki
authors.forename: Naomi
authors.initials: N
authors.lastname: Kawamura
authors.forename: Michio M
authors.initials: MM
authors.lastname: Matsushita
authors.forename: Koichi
authors.initials: K
authors.lastname: Maruyama
authors.forename: Tadashi
authors.initials: T
authors.lastname: Sugawara
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Tsukuda