Predictions of the structural, electronic and thermodynamic properties of the anti-fluorite-type Mg₂Sn under pressure from first principles

Using first-principles calculations based on density functional theory, the structural, electronic and thermodynamic properties of Mg₂Sn in anti-fluorite structure under hydrostatic pressure are investigated. Our results for the equilibrium structural parameters are consistent with the previous experimental and theoretical data. The dependences of elastic constants, polycrystalline elastic moduli, Poisson's ratio and the anisotropy factor on pressure have been investigated. It is found that pressure has a significant effect on elastic properties due to variations in interatomic distances. In addition, the variations in density of states with applied pressure are determined to reveal the bonding characteristics. Finally, the dependences of bulk modulus and thermodynamic properties of Mg₂Sn on pressure and temperature are investigated with the quasi-harmonic Debye model, and the results of thermodynamic properties are consistent with the experimental report. © 2013 The Royal Swedish Academy of Sciences.