Elastic constants and thermophysical properties of CuPd: First-principles study

Based on density functional theory, the structural parameters, elastic moduli and thermophysical properties of Copper-palladium CuPd inter-metallic compound at various temperatures and under high pressures have been studied using first-principles calculations. The pseudopotential-plane wave method within the generalized gradient approximation approach have been utilized to perform the calculations presented in this paper. The material being considered is a pure substance of solid CuPd, arranged in the body centered cubic fashion. The calculated lattice constant is found to be around 3.001 Å, which is in good agreement with the experimental one of 2.96 Å reported in the literature. The elastic stiffness constants are found to increase monotonically and almost linearly with raising pressure. The mechanical stability under compression and the hardness of CuPd are predicted using the elastic constants. Moreover, the isothermal bulk modulus, the constant volume heat capacity, the Debye temperature and the entropy are studied in the pressure range from 0 to 12 GPa and at temperatures ranging from 0 up to 600 K. At room temperature and zero-pressure, the constant volume heat capacity and the entropy are found to be 45.65 and 53.94 J/mol.K, respectively.