Motivated by recent core-level x-ray photoemission spectroscopy (XPS), x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS) experiments for the newly-discovered superconducting infinite-layer nickelate, we investigate the core-level spectra of the parent compounds NdNiO2 and LaNiO2 using the combination of local density approximation and dynamical mean-field theory (LDA+DMFT). Adjusting a charge-transfer energy to match the experimental spectra, we determine the optimal model parameters and discuss the nature of the NdNiO2 ground state. We find that self-doping from the Nd 5d states in the vicinity of the Fermi energy prohibits opening of Mott-Hubbard gap in NdNiO2. The present Ni L3 XAS and RIXS calculation for LaNiO2 cannot explain the difference to NdNiO2 spectra.
@article{arxiv.2105.01248,
title = {Core-Level X-Ray Spectroscopy of Infinite-Layer Nickelate: LDA+DMFT Study},
author = {Keisuke Higashi and Mathias Winder and Jan Kuneš and Atsushi Hariki},
journal= {arXiv preprint arXiv:2105.01248},
year = {2023}
}