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Cu-O network dependent core-hole screening in low-dimensional cuprates: A theoretical analysis

C. Waidacher·J. Richter·K. W. Becker
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Abstract

We analyze the influence of the dimensionality on the Cu 2p_3/2 core level X-ray photoemission spectra of undoped cuprates. Both exchange splitting and delocalization properties are described within one framework using a multi-band Hubbard model. The spectral intensity is calculated by means of the Mori-Zwanzig projection technique for a CuO_4 plaquette ('zero'-dimensional), an infinite CuO_3 chain (one-dimensional), and an infinite CuO_2 plane (two-dimensional). The results are compared to the spectra of Bi_2CuO_4, Sr_2CuO_3, and Sr_2CuO_2Cl_2. Our analysis allows to distinguish between effects of the Cu-O geometry and effects from material-specific properties.

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C. Waidacher, J. Richter, K. W. Becker. 2000-03-11. Cu-O network dependent core-hole screening in low-dimensional cuprates: A theoretical analysis. https://doi.org/10.1103/physrevb.61.13473

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