KTbP_4O_(12)的能级结构及配位场理论计算

本文报告了77K下KTbP_4O_(12)晶体中Tb~(3+)离子~5D_4-~7F_J(J=0～6)跃迁的荧光光谱,并由此得到~5D_4和~7F_J的Stark能级。运用配位场理论对基态谱项~7F_J的Stark能级进行拟合计算,均方根差10cm~(-1),最大偏差24cm~(-1)。

Energy Level Structure of KTbP_4O_12 and Ligand Field Theoretical Calculation

In the present work, the fluorescence spectra of single crystal of KTbP4O12 have been measured at 77K. Most of the observed transitions were identified and the energy level structure of the 7F multiplet was also defined. The coordination of Tb3+ ion by oxygen atoms is eight-fold with the geometry of a slightly distorted square antiprism. In other words, the local symmetry of Tb3+ ion in KTbP4O12 belongs to C4v. There is the same symmetry of Tb3+ ion in TbP5O14. So the symbols of Stark energy levels are of the same as in TbP5O14. The. ligand field calculation was performed for such symmetry and gave a respectab-le to fit the observed Stark splitting of 7F(J = 0-6) multiplet.The comparison between the experimental and the calculated energy level shows that the RMS deviation and the maximum deviation are 10cm-1 and 24cm-1, respectively.