Transition metal ions luminescence in neutron irradiated magnesium oxide

The results of investigation of the photoluminescence (PL), its excitation and optical absorption of MgO crystals doped with different concentrations of transition metals exposed to fast neutron irradiation and after annealing are presented. It is suggested that the 440 nm photoluminescence band belongs to the complex V-OH-Fe3+ center with tetragonal symmetry, the ∼730 nm PL band observed in the irradiated MgO crystals is connected with defects, generated as a result of decay of the complex V-OH-Fe3+ centers. The near infrared luminescence bands in MgO crystals are connected with Fe3+-Fe3+ exchange coupled pairs.