Elasticity and thermodynamic properties of α-Ta4AlC3 under pressure

First-principles calculations of the crystal structure and the elastic properties of α-Ta4AlC3 have been carried out with the plane-wave pseudopotential density functional theory method. The calculated values are in very good agreement with experimental data as well as with some of the existing model calculations. The pressure dependence of the elastic constants cij, the aggregate elastic moduli (B, G, E), the Poisson's ratio, and the elastic anisotropy has been investigated. Using the quasi-harmonic Debye model considering the phonon effects, the temperature and pressure dependencies of isothermal bulk modulus, and the thermal expansions, and Grueneisen parameters, as well as Debye temperatures are investigated systematically in the ranges of 0-60 GPa and 0-1500 K as well as compared to available data.