链状硅酸盐矿物的拉曼光谱研究

Raman Spectroscopic Study of the Chain Silicate Minerals

本文基于密度泛函理论(DFT)的平面波赝势法,利用CASTEP计算模块对四种典型链状(铝)硅酸盐矿物进行拉曼振动活性与拉曼光谱的模拟计算,同时测定了矿物的拉曼光谱,确定了四种矿物拉曼振动谱峰的归属,并结合硅氧四面体应力指数(SIT)进行了分析。结果表明,CASTEP计算模块可以有效获知(铝)硅酸盐矿物特征结构的拉曼振动模式的归属;链状(铝)硅酸盐矿物硅氧四面体局域环境与SiOT非桥氧对称伸缩振动波数之间的关系仍可用SIT指数描述。

Ambient temperature Raman spectra of four typical chain silicate mineral crystals were determined and the vibrational modes have also been simulated through Cambridge Serial Total Energy Package（CASTEP）function based on density functional theory（DFT）.Analysis of the various vibrational modes combined with SIT（stress index of tetrahedron）,which expresses the characteristics of the microstructure of alumina silicates.The results show that the CASTEP calculation is an effective and practical calculation method to simulate Raman spectra of the aluminasilicates,and help to assign the vibrational modes.The concept of SIT also has its application on studying the correlation between Si-Onbsymmetric stretching vibration and the minerals local environment of SiOT.