Probing LaMO₃ Metal and Oxygen Partial Density of States Using X‑ray Emission, Absorption, and Photoelectron Spectroscopy

We examined the electronic structure in LaMO₃ perovskite oxides (M = Cr, Mn, Fe, Co, Ni) by combining information from X-ray emission, absorption, and photoelectron spectroscopy. Through first-principles density functional theory simulations, we identified complementary hybridization features present in the transition metal and oxygen X-ray emission spectra. We then developed a method for the self-consistent alignment of the emission data onto a common energy scale using these features, providing a valuable supplementary technique to photoelectron spectroscopy for studying the partial density of states in perovskites. The combined information from X-ray emission and absorption was used to explore trends in electronic structure characteristics under the Zaanen-Sawatzky-Allen framework - namely the extent of metal-oxygen hybridization, band gap, and charge-transfer gap. We further established a method that allows for the experimental determination of the occupied and unoccupied band positions relative to the oxide Fermi level, as well as on an absolute energy scale. (Figure Presented).United States. Department of Energy (SISGR DE-SC0002633)Skoltech-MIT Center for Electrochemical EnergyNational Science Foundation (U.S.) (ward number DMR-0819762)National Science Foundation (U.S.). Graduate Research Fellowship (Grant No. 1122374)United States. Department of Energy (Contract No. DE-AC02-05CH11231)United States. Department of Energy. Division of Materials Sciences and Engineering (Contract No. DE-AC02-76SF00515