Electronic structure of single-crystal rocksalt CdO studied by soft x-ray spectroscopies andab initiocalculations

Abstract

Soft x-ray emission spectroscopy (XES) and x-ray absorption spectroscopy (XAS) are employed to investigate the occupied and unoccupied electronic structures in rocksalt-phase single-crystal CdO. Resonant XES at the $\mathrm{O}K$ edge reveals a clear $\mathrm{Cd}\phantom{\rule{0.2em}{0ex}}4d--\mathrm{O}\phantom{\rule{0.2em}{0ex}}2p$ hybridized peak and momentum-dependent coherent contributions to the resonant emission spectra. Good agreement is obtained between the above-threshold XES and XAS spectra, and the calculated $\mathrm{O}\phantom{\rule{0.2em}{0ex}}2p$ local partial density of states (PDOS). Calculation of the $\mathrm{O}\phantom{\rule{0.2em}{0ex}}2p$ PDOS was performed within the $GW$ framework of many-body perturbation theory.