Electronic transitions, crystal field analysis and anomalous levels splittings in the optical spectrum of Pr3+ in La2O3 and Pr2O3

A complete account of the electronic transitions observed at 20 and 300 K f or La2O3:Pr3+ (1%) and Pr2O3 in powder and single crystal form in the 4000- 22 000 cm(-1) spectral range is reported. The electronic lines are accompan ied by a number of vibronic sidebands [1]. At 20 K, 42 out of 61 symmetry l evels are determined in the doped sample and 27 in the neat sample. A cryst al field analysis is performed in the theoretical site symmetry C-3v With a nd without 4f(2)/4f 6p configuration interaction. The splittings of the D-1 (2) (1), F-3(2) (3), and H-3(6) (2) levels are examined and discussed in pa rallel with a similar observation made previously on La2O3 :Eu3+ [2] The sp litting is not observed on the crystal. A crystal field analysis is perform ed in a distorted C-1 symmetry affecting the (ff) and the (fp) crystal fiel d parameters. (C) 1999 Elsevier Science B.V. All rights reserved.