Abstract
We report a detailed experimental and theoretical study of the
electronic structure of Mo1−xRex random alloys. We have measured electronic
band dispersions for clean and hydrogen-covered Mo1−xRex (110) with x =
0–0.25 using angle-resolved photoemission spectroscopy. Our results suggest that the bulk and most surface electronic bands shift relative to the Fermi level
systematically and approximately rigidly with Re concentration. We distinguish
and quantify two contributions to these shifts: a raise of the Fermi energy and
an increase of the overall bandwidth. Alloy bands calculated using the firstprinciples
Korringa–Kohn–Rostoker coherent-potential-approximation method
accurately predict both of these effects. As derived from the rigid band model,
the Fermi energy shift is inversely related to the bulk density of states in this
energy region. Using our results, we also characterize an electronic topological
transition of the bulk Fermi surface and relate this to bulk transport properties.
Finally, we distinguish effects beyond the rigid band approximation: a highly
surface-localized state and a composition-dependent impact of the spin–orbit
interaction.
