Optical spectra and analysis for Pr3+ in SrAl12O19

Energy levels of the 4f2 electronic configuration of Pr3+ in SrAl12O19 (SAM) have been determined from polarized absorption and fluorescence spectra using crystals, charge-compensated with Mg2+, at temperatures between about 20 and 300 K. Energy level assignments were made initially by comparing the crystal spectra with energy levels calculated by using crystal-field parameters, Bkm, compatible with those previously reported for Nd3+ in SAM. The Bkm were varied to obtain a best fit between experimental and theoretical energies, and the final values: B20=−94, B40=1047, B60=−1397, and B66=−1245 cm−1 give an rms fit of 14.5 cm−1. The Bkm for Pr3+ in SAM were also used along with a result relating the Bkm to crystal-field components, Anm, derived in a lattice sum calculation to obtain Bkm values for all the triply ionized rare-earth ions in SAM. Odd-fold Akm are also given that are required in the intensity and lifetime calculations and yield results in good agreement with the measurements. In addition, the r...