Computer simulation of the defect pair VPb-VO in PbWO4 crystals

A computer simulation study has been performed to investigate the defects in PbWO4(PWO). The formation energies of isolated point defects VPb″, VO·· and cluster defect VPb″-VO·· pair have been calculated. It is theoretically demonstrated that the most of VO·· in the as-grown PWO crystal exists in the form of the vacancy pair VPb″-VO··, which plays an important role in the formation and transformation process of light induced color centers in the PWO crystal.