Luminescence characteristics of the Pr3+ ion in SrAlF5

The paper reports on a study of luminescence and excitation spectra of SrAlF5:Pr3+ (0.5 mol %) polycrystals performed at 10 and 300 K with synchrotron radiation in the range from 5 to 25 eV. The Pr3+ ions in SrAlF5 were shown to emit successively two photons in transitions from the 1S0 and 3P0 levels. The main energy characteristics of the compound, namely, the position of the 4f → 5d excitation band (5.95–8.0 eV), the energy separation between the 1S0, 4f and the lowest 5d levels (∼0.15 eV), and the SrAlF5 band gap width (∼12 eV), were determined. SrAlF5:Pr3+ was found to possess a number of features not found in other Pr3+-activated fluorides.