Optical polarized properties of the F2 center in YAlO3 crystal

The electronic structures, dielectric functions and absorption coefficient of perfect YAlO3 (YAP) crystal and YAP crystal containing F2 center (YAP:F2) have been studied using the CASTEP code with the lattice structure optimized. The calculated electronic structures indicate that the F2 center in YAP bring donor energy levels in the forbidden band compared with that of perfect YAP. The optical properties of perfect YAP and YAP:F2 show anisotropy and their optical symmetry coincides with the lattice structure geometry. The calculated polarized absorption spectra of YAP:F2 exhibit new absorption bands in the region from 190 to 310 nm, which are in agreement with the experimental results.