Evidence forD-Orbital-Directed X-Ray Photoemission

Abstract
Transition-matrix-element effects are shown to predict the angular variations in the valence-band x-ray-photoemission-spectroscopy (XPS) spectra of copper and gold, while a recently proposed direct-transition model does not. The angular dependence of XPS spectra is directly related to the symmetry properties of the initial-state wave functions. In particular, the t2g and eg projections of metal d bands can be obtained directly from angle-resolved photoemission.