Photoemission and inverse photoemission of transition-metal silicides

Abstract

We present selected results of an experimental and theoretical study of the electronic structure of 3d, 4d, and 5d transition-metal silicides. We have employed x-ray photoemission (XPS) and bremsstrahlung isochromat spectroscopy (BIS) as experimental techniques and calculated the density of states of the compounds in their real crystal structures. The main objective of this paper is to show that by explicit inclusion of the appropriate theoretical solid-state matrix elements for XPS and BIS, we are able to analyze the experimental spectra in detail with respect to the various symmetries contributing to the total spectra. In particular, we obtain information on all the symmetries which are most relevant for the bonding in transition-metal silicides, namely the Si s and Si p states and metal d states. Finally, we compare our XPS results with published photoemission data at lower excitation energy.