First Principle Study of the Physical Properties of Actinide Oxides. A Review

Abstract

Reprocessing spent nuclear fuel creates the conditions for converting nuclear energy to a clean and sustainable energy. Thermal conductors in reactors are molten salts, the safe use of which is based on an accurate knowledge of their thermophysical properties. Due to the difficulty of experimentally measuring these properties, computational methods are coming to the fore. The main component of SNF is uranium dioxide, the change in the structure, energy and electronic properties of which when oxygen is removed from the system and plutonium is added to it was studied using DFT + U calculations. The influence of noble metals present in spent fuel on the process of direct reduction of irradiated nuclear fuel is considered. This work also examines the effects of doping thorium with uranium when Th-U fuel is used in a nuclear reactor. The paper presents data on the calculation of heat capacity, thermal conductivity, elastic moduli and phase transitions occurring in UO2 at high pressures. The thermodynamic stability of actinide oxides is discussed in detail. The ways of improving DFT calculations to increase the accuracy of determining the properties of these nuclear materials are analyzed.