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Single particle spectra of charge transfer insulators by cluster perturbation theory - the correlated band structure of NiO

R. Eder·A. Dorneich·H. Winter
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Abstract

We propose a many-body method for band-structure calculations in strongly correlated electron systems and apply it to NiO. The method may be viewed as a translationally invariant version of the cluster method of Fujimori and Minami. Thereby the Coulomb interaction within the d-shells is treated by exact diagonalization and the d-shells then are coupled to a solid by an extension of the cluster perturbation theory due to Senechal et al. The method is computationally no more demanding than a conventional band structure calculation and for NiO we find good agreement between the calculated single particle spectral function and the experimentally measured band structure.

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R. Eder, A. Dorneich, H. Winter. 2004-09-03. Single particle spectra of charge transfer insulators by cluster perturbation theory - the correlated band structure of NiO. https://doi.org/10.1103/physrevb.71.045105

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