Electronic-structure study of Ni₈₁Cr₁₅B₄ metallic glass using photoemission spectroscopy

Abstract

X-ray- and ultraviolet-photoelectron spectroscopic studies of the core levels and the valence band of amorphous and crystalline (annealed at 800 K) Ni₈₁Cr₁₅B₄ metallic glass are presented, and a comparison has been made of the valence-band spectra with those of the constituent elements. The single broad band appearing in the vicinity of the Fermi level in the spectrum of amorphous Ni₈₁Cr₁₅B₄ is attributed to the d-band combination of both nickel and chromium. The low-lying states arise due to hybridization of metal-metalloid levels. The Ni₃B phase has been detected in crystalline Ni₈₁Cr₁₅B₄. The binding energy changes in the Ni 2p_3/2, Cr 2p_3/2, and B 1s levels, the variation of the Ni 2p_3/2 satellite intensity, and asymmetry-index changes for the core lines have been used to support the above picture as well as to arrive at a comprehensive understanding of the density-of-states variation at the Fermi level. The charge-transfer mechanism between constituent elements in metallic glasses is also discussed.