Electronic structures and heterogeneity of Zr-Cu-Ag metallic glasses

Abstract

Photoemission and inverse-photoemission spectroscopy (PES and IPES) measurements were carried out on Zr50Cu50, Zr45Cu45Ag10, and Zr40Cu40Ag20 metallic glasses to investigate the valence- and conduction-band electronic structures, respectively. From the incident photon energy, hν dependence of the PES spectra, partial DOSs of s and d electrons for the constituent elements were estimated, and it was found that the DOS near EF is mainly composed of Zr 4d electrons and the Cu 3d electrons are localized in the valence band. Core-level PES measurements were also performed at the Zr 3d, Cu 3p, and Ag 3d levels. The Zr 3d core spectra indicate three chemical states in all of these glasses, suggesting a chemical heterogeneity. Energy shifts are observed in the Zr 3d core levels, indicating the charge transfer in the Zr-Cu-Ag metallic glass system.