Theoretical Prediction on Mechanical, Dynamic, and Thermodynamic Properties of C11b-Structured WSi2 under Pressure

Abstract

Abstract The structural parameters, mechanical, dynamic, and thermodynamic properties of WSi2 with the C11b structure under pressure were systematically explored by using first-principles calculations. The results shown that calculated lattice constants and elastic constants of WSi2 were consistent with previous experimental findings and theoretical values. Our obtained elastic constants revealed that WSi2 was mechanically stable from 0 to 100 GPa. The values of anisotropic indexes, three-dimensional surface constructions, and two-dimensional projections under pressure indicated that WSi2 showed mechanical anisotropy. Additionally, the phonon density of state and phonon dispersion curves under pressure were obtained, and all vibration modes were analyzed. Finally, thermodynamic properties were also predicted based on quasi-harmonic approximation.