Structural, magnetic, mechanical, thermodynamic, and electronic properties of PuAlO3: A first-principles study

Abstract

Based on the Coulomb hybrid density functional with spin–orbit coupling (SOC) effect and generalized gradient approximation (GGA) + U method, the structural, magnetic, and electronic properties of PuAlO3 (Pnma and Imma) have been studied. The value of magnetic moment (μs) with the GGA + U method is maximum, the GGA + U + SOC method is minimum, and the GGA method is centered. The phonon curve of the two phases with ferromagnetic (FM) is almost identical to that of the antiferromagnetic (AFM) state. Pu atoms primarily contribute to the low-frequency phonon branches. In contrast, lighter O atoms are mainly responsible for the high-frequency phonon modes, and Al atoms are predominantly distributed in the middle part of the compound. For the mechanical properties, the volume modulus B of the V-R-H scheme agrees with the Birch–Murnaghan equation of state fitting results. Moreover, the bulk modulus is anisotropic, and the remaining parameters are isotropic. According to the electronic calculation, FM has a wider bandgap than AFM. In part of the state density diagram, it can be observed that the main contributors are Pu and O atoms. Bader charge calculation revealed that the charge of Pu and Al atoms transfers to O atoms.