Zhang-Rice singlet-state formation by oxygen 1s resonant x-ray emission in edge-sharing copper-oxide systems -: art. no. 045103

Resonant behavior of O 1s x-ray emission spectrum (XES) in Cu-based oxides, such as CuGe3 and Li2CuO2, is investigated through the model calculations using an edge-sharing Cu2O6 cluster. It is shown that the inelastic peaks that originate from the Cu d-d excitations and the Zhang-Rice singlet excitation can be observed on resonance, which indicates the importance of the many-body effects in discussing the O 1s resonant XES. It is shown that the Zhang-Rice singlet state can be excited in the O 1s XES final state when the Cu spins configuration around the irradiated O site is antiferromagnetic. Therefore the experiment at low temperatures is highly desired.