摘要
The polarized absorption spectra of trigonal single crystal Ndb>0.5b>Gdb>0.5b>Feb>3b>(BOb>3b>)b>4b> were measured in the spectral range 10,000-22,000 cmp>鈭?p>. The d-d and f-f transitions spectra were separated. The f-f transitions intensities were analyzed in terms of the Judd-Ofelt theory in a ferroborate with huntite structure for the first time, and the following parameters of the theory were obtained: 惟b>2b> = 4.4 脳 10p>鈭?0p> cmp>2p>, 惟b>4b> = 8.04 脳 10p>鈭?0p> cmp>2p>, and 惟b>6b> = 8.25 脳 10p>鈭?0p> cmp>2p>. The strengths, spontaneous emission probabilities, branching ratios, spectroscopic quality factor and excited state lifetime were calculated for transitions from the p>4p>Fb>3/2b> state to p>4p>Ib>Jb> manifold. All the obtained spectroscopic characteristics were compared with those of alumoborates with the same crystal structure.