First-principles study of the electronic and optical properties of rutile TiO2

The electronic, structural properties and optical properties of the rutile TiO2 have been reported using the full potential linearized augmented plane wave (FP-LAPW) method as implemented in the WIEN2K code. We employed the generalized gradient approximation (GGA), which is based on exchange-correlation energy optimization to calculate the total energy. Also we have used the Engel–Vosko GGA formalism, which optimizes the corresponding potential for band structure calculations. Our results including lattice parameter, bulk modulus, density of states, the reflectivity spectra, the refractive index and band gap are compared with the experimental data. We present calculations of the frequency-dependent complex dielectric function ε(ω)ε(ω) and its zero-frequency limit ε1(0)ε1(0).