Theoretical investigation of the mechanical and thermodynamics properties of Nb₃Ga superconductor under pressure

The mechanical and thermodynamics properties of Nb₃Ga under pressure have been studied and analyzed using first-principles combined with quasi-harmonic Debye model. The calculated lattice parameter of the ground state is in well agreement with the experimental data. The pressure dependence of a/a₀ and V/V₀ are investigated, the bulk modulus B₀ and its pressure derivative B^′ are found to be 164.5 GPa and 3.936, respectively. The elastic constants under pressure are obtained and the polycrystalline elastic moduli of Nb₃Ga are calculated derived from the single-crystal elastic constants. The results show that Nb₃Ga is stable and behaves in a ductile manner up to 40 GPa. In addition, the elastic anisotropy, Vickers hardness as well as the melting temperature of Nb₃Ga are investigated. Finally, the pressure and temperature dependence of the thermodynamic properties are also been obtained in the ranges of 0–40 GPa and 0–1000 K through the quasi-harmonic Debye model. - Highlights: • The physical properties of Nb₃Ga were investigated. • The bulk modulus B₀ and its pressure derivative B^′ are found to be 164.5 GPa and 3.936. • The Nb₃Ga is stable and behaves in a ductile manner up to 40 GPa. • The temperature dependence of the thermodynamic properties is obtained. • The 3D figures of the Young's modulus for Nb₃Ga are obtained under pressure