Density functional theory: The evaluation of structural, electronic, optical, and mechanical properties of WO3

A transition metal oxide semiconductor WO 3 has an indirect bandgap, and this bandgap energy is significantly improved by non-hybrid functional, especially in PBE0. The electronic bandgap calculated is in good agreement with the experimental value. Our partial density of state (PDOS) analysis accurately describes the electronic structure of the material: the conduction band is made of W–O antibonding states and the valence band mainly contributes to the O nonbonding orbitals. A high absorption coefficient of > 10 4 cm −1 and 70% of the light being reflected have been reported in this work. We also carried out our investigation on elastic and mechanical properties, and we found that our WO 3 is determined to be brittle and ionic covalent. Our work here is dedicated to obtaining a self-consistent interpretation and prediction of the structural, electronic, optical, and mechanical properties of a transition-metal oxide compound.