Elasticity under pressure and thermal property of Mg₂La from first-principles calculations

Abstract

The elastic properties, thermodynamic and electronic structures of Mg₂La were investigated by using first-principles. The calculated results show that pressure affects the elastic constants of C₁₁ more than that of C₁₂ and C₄₄. Specifically, higher pressure leads to greater bulk modulus (B), shear modulus (G), and elastic modulus (E). We predict B/G and anisotropy factor A based on the calculated elastic constants. The Debye temperature also increases with increasing pressure. Based on the quasi-harmonic Debye model, we examined the thermodynamic properties. These properties include the normalized volume (V/V₀), bulk modulus (B), heat capacity (C_v), thermal expansion coefficient (α), and Debye temperature (Θ). Finally, the electronic structures associated with the density of states (DOS) and Mulliken population are analyzed.

Keywords

first-principles / elastic properties / thermodynamics properties / electronic structure

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