Electronic structure of UO2.12 calculated in the coherent potential approximation taking into account strong electron correlations and spin-orbit coupling

Abstract

Based on the coherent potential approximation, the method of calculating the electronic structure of nonstoichiometric and hyperstoichiometric compounds with strong electron correlations and spin-orbit coupling has been developed. This method can be used to study both substitutional and interstitial impurities, which is demonstrated based on the example of the hyperstoichiometric UO_2.12 compound. The influence of the coherent potential on the electronic structure of compounds has been shown for the nonstoichiometric UO_1.87 containing vacancies in the oxygen sublattice as substitutional impurities, for stoichiometric UO₂ containing vacancies in the oxygen sublattice and oxygen as an interstitial impurity, and for hyperstoichiometric UO_2.12 with excess oxygen also as interstitial impurity. In the model of the uniform distribution of impurities, which forms the basis of the coherent potential approximation, the energy spectrum of UO_2.12 has a metal-like character.