Ab Initio Calculation of Structural and Thermodynamic Properties of Nb₂AsC

The structural and thermodynamic properties of Nb₂AsC have been investigated with the first-principles density functional theory computations. The calculated equilibrium structural parameters agree well with the available experimental and theoretical values of Medkour et al. The calculated elastic constants are in excellent agreement with the theoretical values at ambient pressure. The elastic constant indicates that hexagonal structure Nb₂AsC is mechanically stable at ambient pressure. Also, the elastic anisotropy is examined through the computation of the Young's modulus. Based on quasi-harmonic Debye model, the thermodynamic properties including the adiabatic bulk modulus, thermal expansion coefficient, Debye temperature and heat capacity at constant volume under high temperature and pressure are predicted.