Electronic structure and optical properties of 1T-TiS2 and lithium intercalated 1T-TiS2 for lithium batteries.

We report results of first-principles calculations of electronic and optical properties of pristine 1T-TiS(2) and 1T-TiS(2) intercalated with lithium. Calculations have been performed using the full-potential linearized augmented plane wave method based on density functional theory together with the local density approximation for the exchange correlation energy functional. We have calculated the band structure, density of states, and the linear optical properties. We compare our results of the intercalated 1T-LiTiS(2) with the host 1T-TiS(2) to ascertain the effect of Li intercalation on the electronic and optical properties. The Li-s and Li-p bands are very broad and do not contribute much to the density of states. Our calculations show that the electronic and optical properties are influenced significantly when TiS(2) is intercalated with lithium.