Partial density of occupied valence states by x-ray standing waves and high-resolution photoelectron spectroscopy

We introduce an experimental method by which site-specific valence-electronic structure may be obtained. It utilizes the spatial dependence of the electric-field intensity that results from the superposition of the incident and reflected x-ray beams within the vicinity of a crystal x-ray Bragg reflection. Resolution of the anion and cation contributions to the GaAs valence band is demonstrated and compared to an ab initio theoretical calculation of the Ga and As partial density of states.