磷灰石晶格喇曼活性外振动的实验研究

An Experimental Investigation for the Apatite Lattice Vibration by Raman-Activation

为了对氟磷灰石晶格外振动模式进行研究,以全面了解磷灰石的晶体振动特征,在理论预测的基础上,用偏振喇曼光谱技术,对人工合成的氟磷灰石单晶体进行了实验测试。共实测出10个喇曼活性外模式;分别位于313、287、273、231、211、181、174、135、100和70 cm-1处。用偏振定向下模式禁忌推断的方法,并与内模式的文献结果进行对比,首次对外模式进行了群论指派,上述晶格模式可以表示为R=2Ag+5E2g+3E1g。其中,Ag模式强度最大,属全旋转群,与晶体的定向无关,表明该振动引起最大的极化率变化。

In order to understand the crystal vibration behavior of apatite, the Raman activated lattice modes of synthetic fluor apatite crystal were measured by single-crystal polarized Raman spectroscopy. Based on the group-theoretical prediction, 10 Raman-activated lattice modes were recorded in positions of 313,287,273,231,211,181, 174,135,100 and 70cm-1 respectively. In comparison with the previous research results of Raman-activated inner-modes of same mineral, the external lattice mode has been firstly assigned based on the group theory. The above lattice modes could be expressed as R = 2Ag + 5E2g + 3E1g The A, mode vibration, which occurred in all orientations, is the most intensive one among all modes and caused the maximum variation of polariz ability of the fluor-apatite crystal.