Electronic structure, elastic and thermodynamic properties of α-phase Na3N under pressure from first principles

The structural, electronic, elastic and thermodynamic properties of α-phase Na3N under pressure are investigated by performing first principles calculations within generalized gradient approximation. The elastic constants, bulk modulus, shear modulus, Young's modulus, and Poisson's ratio dependencies on pressure are also calculated. The thermodynamic properties of the α-phase Na3N are calculated using the quasi-harmonic Debye model. The dependencies of the heat capacity and the thermal expansion coefficient, as well as the Grüneisen parameter on pressure and temperature are investigated systematically in the ranges of 0-1 GPa and 0-100 K.