X-ray spectroscopy of the rare-earth nickelate LuNiO3: LDA+FDMFT study

We present a computational study of resonant inelastic x-ray scattering (RIXS) and x-ray absorption in a representative rare-earth nickelate LuNiO3. We study the changes in the spectra across the metal-insulator/site-disproportionation transition. In particular, we address the question of site selectivity of the two methods in the disproportionated insulating phase and the signature of metal-insulator transition in the fluorescencelike feature of the RIXS spectra. To this end we use the local-density approximation + dynamical mean-field theory approach combined with the configuration integration method to compute the core-level spectra.