X-ray photoemission spectra of the valence bands of the3dtransition metals, Sc to Fe

Abstract

High-resolution x-ray-photoemission valence-band (VB) spectra are presented of the $3d$ transition metals, Sc to Fe. The measurements were conducted under ultra-high-vacuum conditions using polycrystalline samples. In the hcp elements Sc and Ti the main peaks in the valence bands are identified and compared with the results of band-structure calculations. Some rigidity is observed in the Sc and Ti bands as well as in the V and Cr bands. The expected two-peak structure for V and Cr is observed. In chromium we also observed a relatively low density of states at the Fermi energy. The VB spectrum for chromium is compared to theoretical predictions, and we present an assignment of the Cr symmetry-point energies. Our valence-band spectrum of Mn is quite similar to that of H\"ufner and Wertheim and our spectrum of Fe is in good agreement with that observed by H\"ochst, Goldman, and H\"ufner. These iron VB spectra agree qualitatively with expectations based on band models of ferromagnetism. It is observed that the VB spectrum of bcc iron may be constructed to agree within an energy scale factor from two bcc Cr VB's shifted to account for spin polarization. We also deduce the symmetry-point energies in iron.