Defect Chemistry and Electronic Structure of α-Pu2O3: A Hybrid DFT Study of Charged Vacancies, Interstitials, and Antisites

Using state-of-the-art hybrid density functional theory, we systematically investigate the formation energetics and electronic structure of native charged point defects in α-Pu2O3, including plutonium and oxygen vacancies, interstitials, and antisite defects. We find that these defects induce significant local structural distortions and modify the magnetic properties of neighboring Pu ions. Furthermore, they lead to a redistribution of electronic states near the band edges and induce in-gap states, resulting in notable variations of the band gap. Defect formation energetics are found to be strongly governed by both the chemical potentials of the constituent elements and the electron chemical potential, resulting in distinct defect stability regimes under different chemical potential conditions. These defects, in general, are found to generate deep electronic levels within the band gap, suggesting their potential role as carrier trapping centers. Overall, this study provides critical insight into the role of point defects in α-