title: Onset of metallic behavior in magnesium clusters.
abstract: We have measured the photoelectron spectra of mass-selected magnesium cluster anions, Mg- n, over the size range, n=3-35. Their s-p band gaps were observed to close at n=18, signaling the onset of metallic behavior. Electronic shell structure was implicated by gap "reopenings" and mass spectral magic numbers. Complementary calculations are presented in the companion paper [P. H. Acioli and J. Jellinek, Phys. Rev. Lett. 89, 213402 (2002)]].
authors.affiliation: Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA.
authors.forename: Owen C
authors.initials: OC
authors.lastname: Thomas
authors.forename: Weijun
authors.initials: W
authors.lastname: Zheng
authors.forename: Shoujun
authors.initials: S
authors.lastname: Xu
authors.forename: Kit H
authors.initials: KH
authors.lastname: Bowen
authors.forename: Moshe
authors.initials: M
authors.lastname: Shiloh