Accurate determination of quasi-particle electronic and optical spectra of anatase titanium dioxide

The electronic structure and quasi-particle absorption spectra of anatase titanium dioxide has been calculated by employing state of the art density functional theory(DFT) and Many-Body Perturbation Theory methods(MBPT) within the framework of Hybrid Density Functional(HSE). GW methods are used in combination with Bethe-Salpeter Equation (BSE) to determine the Quasi Particle energy levels and the role of excitons in optical absorption spectra. Accurate optical and electronic band gap are determined from these methods. In addition to it an analysis of charge redistribution within the anatase unit cell is also presented within the PBE - DFT to analyze the orbital hybridization patterns and the character of chemical bonds.