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Dynamical electron correlations in metals: TB-LMTO and multiband Hubbard Hamiltonian

V. Drchal·V. Janis·J. Kudrnovsky
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Abstract

We study electronic properties of solids with correlated d electrons which could be described by a multiband Hubbard Hamiltonian in the weak-interaction case, $U/w<1$. The one-electron part of the many-body Hamiltonian is described by a tight-binding LMTO method. The many-body part is treated by non-selfconsistent FLEX-type approximations with adjusted chemical potential not to change the LMTO band filling. The calculated DOS gets narrower but is only little influenced by electron correlations at the Fermi energy. A precursor of a satellite band in the paramagnetic bcc Ni is found at about 6 eV below the Fermi level in agreement with experiment.

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V. Drchal, V. Janis, J. Kudrnovsky. 1998-10-15. Dynamical electron correlations in metals: TB-LMTO and multiband Hubbard Hamiltonian. https://arxiv.org/abs/cond-mat/9810181

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