An exhaustive analysis of the structural, electronic, magnetic, mechanical, thermal, thermoelectric, optical and thermodynamic properties of AMnBi2 (A = Ca and Sr) via DFT+U and Monte Carlo simulations

Abstract

Ab initio calculations are used in the present study to analyze the structural, magnetoelectronic, mechanical, thermal, thermoelectric, optical and thermodynamic properties of AMnBi2 compounds (where A = Ca and Sr). The calculations use the density functional theory involving the Full Potential –Linearized Augmented Plane. Wave and the Monte Carlo simulation. We have used the Generalized Gradient Approximation (GGA) with Perdew-Burke-Ernzerhof (PBE) functional for modelling the exchange-correlation potential with Hubbard correction (GGA + U) was employed. The bulk modulus, its first derivative, and the optimal lattice parameters have been found. Both compounds display metallic nature. The electronic transport coefficients have been calculated. The entropy, thermal expansion coefficient, Debye temperature, and heat capacities Cv and Cp are calculated. The elastic constants at zero pressure, the bulk modulus B, and the shear modulus G have been evaluated. The Young's modulus and Poisson's ratio of two compounds have been performed. The Debye temperature is also approximated from the average sound velocity. The Néel temperature, magnetization, and hysteresis cycles are found.