橄榄石原位高温拉曼光谱研究

利用微型电阻丝加热装置产生高温, 采用镍铬热电偶探测样品的温度, 在273～1 113 K温度范围，对橄榄石晶体进行了原位高温拉曼光谱研究。拉曼光谱数据显示：Si-O伸缩振动模高于800 cm^-1，Si-O弯曲振动模为400～700 cm^-1，SiO₄四面体旋转振动模和金属-氧的平移振动模低于400 cm^-1；得到了橄榄石拉曼振动频率随温度的变化关系，首次发现了橄榄石常温频率为541 cm^-1的Si-O反对称弯曲振动的A_g模,比其它的振动频率有较弱的温度效应。

In-Situ Raman Study of Olivine Under High Temperature

In-situ Raman spectra of olivine have been studied at temperatures 273 K to 1 113 K and at ambient pressure using resistance-wire heating.Temperature of the sample was measured by an alumel-chromel thermocouple.The Raman study reveals that the Si-O stretching modes above 800 cm~(-1);the Si-O bending modes between 400 cm~(-1) and 700 cm~(-1);SiO_4 rotation and metal-oxygen translation modes below 400 cm~(-1).The authors determined the temperature dependences of the Raman bands of olivine and observed for the first time that the Si-O bending modes corresponding to the ambient 541cm~(-1) band have a weaker temperature effect than other bands.