铝硅酸盐矿物的Raman振动特征解析

RAMAN ACTIVE VIBRATIONS OF ALUMINOSILICATES

分别测定了蓝晶石、红柱石和夕线石3种铝硅酸盐天然矿物晶体的Raman光谱,并利用Materials Studio3.0软件计算3种矿物的Raman振动频率,分析其简正振动模式,确定了三种矿物特征谱峰的归属,解析了铝对铝硅酸盐Raman光谱振动特征的影响。结果表明:随着四配位铝的增加(从蓝晶石、红柱石到夕线石),800～1200cm-1波数区间内谱峰频率降低,该区间的谱峰归属于Si—Onb间非桥氧对称伸缩振动;700～800cm-1区间内出现的谱峰归属于Al—Onb间非桥氧的对称伸缩振动。当铝全部为六配位时,会引起800～1200cm-1区间内的谱峰向高频方向迁移。这为进一步利用Raman光谱来研究硅酸盐玻璃和熔体结构中铝的作用提供了重要依据。

Raman spectra of aluminosilicate minerals of kyanite, andalusite, and sillimanite were determined. The Raman vibration frequencies of the three minerals were calculated by Materials Studio 3.0 software. The normal mode of vibration was analyzed, and description of the characteristic peak of the three minerals was confirmed. The effects of Al content on Raman spectra of aluminosilicate minerals were investigated. The result shows that there is a decreasing tendency in frequencies ranging from 800-1200 cm^-1 with the increasing of four-coordinated Al content, and Raman scattering bands in the range were assigned to Si-Onb symmetric stretching vibrations. Raman bands in the range of 700-800 cm^-1 can be attributed to Al-Onb symmetric stretching vibrations. The Raman bands in the range of 800-1200 cm^-1 shift to a higher frequency with all the Al acting as six-coordinate cation.