Insights into the Effect of Vacancies on the Stability, Mechanical, Electronic, Thermodynamic, and Optical Properties of C40‐WSi₂ Using First‐Principles Studies

Herein, the effect of different atomic vacancies on the properties of C40‐type WSi 2 are investigated. The formation energy, elastic properties, phonon, electronic structure, thermodynamic, and optical properties of C40‐type WSi 2 are calculated. Calculations reveal that W vacancies are more likely to form in WSi 2 , and no imaginary phonon frequencies are detected in the phonon dispersion curves. Vacancies slightly enhance the ductility of C40 WSi 2 , with W vacancies performing better than Si vacancies. These vacancies weaken the W—Si and Si—Si bond strengths, affecting the elastic modulus but increasing the ductility of WSi 2 . The electronic properties indicate that C40‐WSi 2 is a semiconductor. From the electronic structure analysis, it is clear that the W atomic vacancy can transform WSi 2 from semiconducting‐to‐metallic properties. The effects of vacancies on the thermodynamic and optical properties of WSi 2 are explored. This research contributes to the development of excess metal silicides as potential high‐temperature materials for later use.