A first-principles study on point defects in plutonium dioxide

Plutonium dioxide is one of the main components of nuclear fuels. In this paper, we evaluated formation energies of charged vacancies and site-interstitial atoms in plutonium dioxide based on density functional theory with spin-orbit coupling and strongly-correlated electron effect using LDA+U method. We also estimated migration energies of oxygen defects. We found that oxygen vacancies with double positive charge and interstitials with double negative charge are the most stable and that the calculated migration energy of an oxygen vacancy is comparable with that of an oxygen interstitial.