Theoretical study of elastic and thermodynamic properties of CuSc intermetallic compound under high pressure

Abstract

The structural, mechanical and thermodynamic properties of copper scandium CuSc intermetallic compound under temperature and pressure have been investigated using the plane wave (PW) - pseudopotential (PP) approach in the framework of the density functional theory (DFT). The structural parameters at equilibrium, the elastic moduli, the mechanical stability criteria and the sound velocity are studied in the pressure range 0–12 GPa. In addition, the heat capacity, the Grüneisen parameter, the Debye temperature, the entropy, and the thermal expansion coefficient are studied for temperatures ranging from 0 up to 1000 K. The equilibrium lattice parameter found is around 3.261 Å. It is in good agreement with the experimental one of 3.25 Å reported in the literature. According to the generalized elastic stability criteria, we predict the occurrence of a phase transition of the B2-type structure at 25.5 GPa. At room temperature and zero-pressure, the isothermal bulk modulus and the Grüneisen parameter found were 80.86 GPa and 2.04 respectively.