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A new hybrid LDA and Generalized Tight-Binding method for the electronic structure calculations of strongly correlated electron systems

V. A. Gavrichkov·M. M. Korshunov·S. G. Ovchinnikov·I. A. Nekrasov·Z. V. Pchelkina·V. I. Anisimov
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Abstract

A novel hybrid scheme is proposed. The {\it ab initio} LDA calculation is used to construct the Wannier functions and obtain single electron and Coulomb parameters of the multiband Hubbard-type model. In strong correlation regime the electronic structure within multiband Hubbard model is calculated by the Generalized Tight-Binding (GTB) method, that combines the exact diagonalization of the model Hamiltonian for a small cluster (unit cell) with perturbation treatment of the intercluster hopping and interactions. For undoped La$_2$CuO$_4$ and Nd$_2$CuO$_4$ this scheme results in charge transfer insulators with correct values of gaps and dispersions of bands in agreement to the ARPES data.

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V. A. Gavrichkov, M. M. Korshunov, S. G. Ovchinnikov, I. A. Nekrasov, Z. V. Pchelkina, V. I. Anisimov. 2005-05-13. A new hybrid LDA and Generalized Tight-Binding method for the electronic structure calculations of strongly correlated electron systems. https://doi.org/10.1103/physrevb.72.165104

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