First principle studies on the optical properties of PbWO4 crystal with oxygen vacancy VO2+

The electronic structures, dielectric function, complex refractive indices and absorption spectra of the perfect PbWO4 crystal and the crystal containing oxygen vacancy VO2+ have been calculated using full-potential (linearized) augmented plane-wave (LAPW) + local orbitals (lo) method with the lattice structure optimized. The results indicate that the perfect PWO crystal does not occur absorption band in the visible and near-ultraviolet region. However, the calculated absorption spectrum of the PWO crystal containing VO2+ has two bands peaking at 370nm and 420nm in the visible and near-ultraviolet region respectively. It reveals that the 350nm and 420nm absorption bands are related to the existence of VO2+ in the PWO crystal.