摘要
本文对新型非线性晶体二水硝酸镧钾［Ｋ２Ｌａ（ＮＯ３）５·２Ｈ２Ｏ］的晶格振动进行了群论分析．给出了该晶体在 点晶格振动的对称性分类．它们是４２Ａ１＋４２Ａ２＋４５Ｂ１＋４５Ｂ２其中声学校为Ａ１＋Ｂ１十Ｂ２．拉曼活性模为４ｌＡ１＋４２Ａ２＋４４Ｂ１＋４４Ｂ２，红外活性模为习４１Ａ＋４４Ｂ１＋４４Ｂ２．测量了该晶体不同几何配置的拉曼光谱，利用群论分析结果对谱图进行了识别和讨论．
Abstract Lattice vibrations of the K2La(NO3)5. 2H2O crystal arc analysed with the aid of group theory. The vibrations of species are given. They are 42A1+42A2+45B1+45B2. The Al, B1 and B2 arc acoustic modes. The 41Al, 42A2, 44B1 and 44B2 modes are Raman active. The 4lAI、44B1. 44B2 modes are IR active. The Raman spectra of the crystal are observed in different grometric configrations. The experiment results arc analyst and discussed.
