A First-Principles Calculation on Structural, Electronic, Magnetic, Mechanical, and Thermodynamic Properties of SrAmO3

Abstract

For the first time, the americium-based perovskite SrAmO3 has been studied with respect to its structural, electronic, magnetic, mechanical, and thermodynamic properties. The study has been carried within the well-known density functional theory (DFT) using different approximations such as local spin density approximation (LSDA), generalized gradient approximation (GGA), LSDA + U, GGA + U. In order to check for the stable ground state, optimization was performed for non-magnetic, ferromagnetic, and anti-ferromagnetic phases, and the compound was found to be stable in the ferromagnetic phase. The spin magnetic moment was obtained with different exchange correlations and was found to be an integer which is one of the consequences of half-metallic nature. The half-metallic nature of SrAmO3 was also confirmed from spin-polarised band structure calculations using GGA, GGA + U, and mBJ, showing metallic nature in spin-up states and semi-conducting in spin-down states. The elastic constants, Young modulus, shear modulus, Poisson ratio, and anisotropic factor were also calculated. SrAmO3 was found to establish ductile and anisotropic nature. Debye temperature was predicted to be 353 K from elastic constants. The thermodynamic properties, like variation of specific heat capacity, thermal expansion, and entropy, were studied in the temperature range of 0 to 600 K.