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arXiv · 0708.0337

Revisiting the valence-band and core-level photoemission spectra of NiO

M. Taguchi·M. Matsunami·Y. Ishida·R. Eguchi·A. Chainani·Y. Takata·M. Yabashi·K. Tamasaku·Y. Nishino·T. Ishikawa·Y. Senba·H. Ohashi·S. Shin
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Abstract

We have re-examined the valence-band (VB) and core-level electronic structure of NiO by means of hard and soft x-ray photoemission spectroscopy (PES). The spectral weight of the lowest energy state found to be enhanced in the bulk sensitive Ni 2p core-level PES. A configuration-interaction model including the bound state screening has shown significant agreement with the core-level spectra, and the off and on-resonance VB spectra. These results identify the lowest energy state in core-level and VB-PES as the Zhang-Rice doublet bound state, consistent with the spin-fermion model and recent ab initio calculation with dynamical mean-field theory (LDA + DMFT).

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M. Taguchi, M. Matsunami, Y. Ishida, R. Eguchi, A. Chainani, Y. Takata, M. Yabashi, K. Tamasaku, Y. Nishino, T. Ishikawa, Y. Senba, H. Ohashi, S. Shin. 2008-05-20. Revisiting the valence-band and core-level photoemission spectra of NiO. https://doi.org/10.1103/physrevlett.100.206401

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