Radiation defects in LiBaF3 perovskites

We investigated the electron paramagnetic resonance (EPR), recombination afterglow, thermostimulated luminescence (TSL) and absorption of LiBaF3 perovskites crystals X-irradiated at 80 K The self-trapped hole centre V-K(F-2(-)) oriented along the [110] axis and electron F type (F-A) centres are identified. X-irradiation at temperatures below 200 K results in creation of a long-term temperature-independent afterglow- tunnelling luminescence (TL), with main emission bands at 300, 370 nm and 430 nm. The short wavelength TL bands are associated with the tunnelling recombination of the F type centre with the V-K centre. The thermal stability of V-K centre is estimated to be about 130 K.