Mapping the conduction band edge density of states of γ-In₂Se₃ by diffuse reflectance spectra

It is demonstrated that the measured diffuse reflectance spectra of γ-In₂Se₃ can be used to map the conduction band edge density of states through Kubelka-Munk analysis. The Kubelka-Munk function derived from the measured spectra almost mimics the calculated density of states in the vicinity of conduction band edge. The calculation of density of states was carried out using first-principles approach yielding the structural, electronic, and optical properties. The calculations were carried out implementing various functionals and only modified Tran and Blaha (TB-MBJ) results tally closest with the experimental result of band gap. The electronic and optical properties were calculated using FP-LAPW + lo approach based on the Density Functional Theory formalism implementing only TB-mBJ functional. The electron and hole effective masses have been calculated as $me*=0.25m0$ and $mh*=1.11m0$⁠, respectively. The optical properties clearly indicate the anisotropic nature of γ-In₂Se₃.