Study of electronic structure, elastic and thermodynamic properties of Cu₂MgSnS₄ under different pressures

The electronic structure, elastic and thermodynamic properties of Cu2MgSnS4 was studied based on density functional theory (DFT). The results show that Cu2MgSnS4 is a direct bandgap semiconductor. The B/G of Cu2MgSnS4 is greater than 1.75, indicating that Cu2MgSnS4 is a ductile material. Through the study of thermodynamic properties, it is found that the temperature increases, the bulk modulus B and Debye temperature 0 decrease, while the heat capacity C-V, entropy S, Gruneisen constant gamma and thermal expansion coefficient alpha increase, and the heat capacity is close to the Dulong-Petit limit. As the pressure increases, the bulk modulus B, Debye temperature 0 increases, while the entropy S, Gruneisen constant gamma and heat capacity C-V decrease.