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

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 نشر من قبل Munetaka Taguchi Dr
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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