Theoretical investigation on the elastic and thermodynamic properties of CuInS2

The first-principles method based on the density functional theory is used to investigate the properties of chalcopyrite CuInS2 crystal. The crystal structural parameters are optimized, and the elastic constants and bulk modulus are also calculated, and the results are highly consistent with those in the literature. The stability of the crystal is judged from the Born stability criteria. Based on the quasi-harmonic Debye model, the pressure and temperature dependencies of the bulk modulus, the Debye temperature, the Gr?neisen parameter, and the thermal expansion coefficient are obtained.