Research on the optical spectra, g factors and defect structures for two tetragonal Y2+ centers in the irradiated CaF2: Y crystal

► Optical and EPR spectra of two Y2+ centers in CaF2 are calculated. ► The calculations are from CDM and PTM methods. ► Calculated results from both methods show good agreement with observed values. ► The defect models and defect structures of both Y2+ centers are obtained.