First-principles calculations of phonon and thermodynamic properties of OsSi2

The structure, lattice dynamics, and some thermodynamic properties of orthorhombic OsSi2 were investigated using a first-principles density functional theory (DFT). Linear response theory was used to calculate the phonon dispersion relation and phonon density of states for OsSi2 as well as its infrared and Raman active mode frequencies. In this study, the thermodynamic properties, including vibrational entropy (Svib), constant-volume specific heat (Cv), and Debye temperature (ΘD), were predicted theoretically and discussed.