Infrared reflectivity and lattice fundamentals in anatase TiO2

Abstract

Polarization-dependent far-infrared reflectivity measurements were carried out on single crystals of anatase TiO2. The results were analyzed to yield the dielectric dispersion properties of anatase in the lattice fundamentals regime. The frequencies (in cm(-1)) of the transverse optical (TO) and longitudinal optical (LO) zone-center phonons were determined to be 367(755) for the TO (LO) of the A(2u) mode, 262(366) and 435(876) for the E(u) modes. The large TO-LO splittings were used to estimate effective charges.