CaSiO_3从熔体到玻璃的结构和拉曼光谱性质研究  

Theoretical Study of Structural and Raman Spectral Properties of CaSiO_3 Quenched from Melt to Glass

作　　者：吴永全 尤静林 蒋国昌 陈辉 

机构地区：[1]上海市现代冶金与材料制备重点实验室,上海200072

出　　处：《无机化学学报》2004年第2期133-138,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金资助项目(No.59832080和No.59874016);上海市新材料研究中心资助项目(No.98JC14018)。

摘　　要：采用分子动力学模拟以及一种计算拉曼谱的新方法研究了CaSiO3从高温熔体淬火到室温玻璃态的过程中微结构性质和拉曼谱的变化。在结构变化中,主要是键长随温度的降低而缩短,并且Si鄄Ob键长的下降幅度明显比Si鄄Onb的下降幅度大,另外Si鄄Ob和Si鄄Onb两种键的物质的量分数的变化说明温度的降低使体系的无序度降低。随着温度的降低,偏拉曼谱中表征5种Qi的强特征峰的频率都呈上升趋势,而且基本与温度呈一个直线关系。计算结果还证实,温度对拉曼散射系数没有影响。得到的拉曼散射系数的两个比值分别为:S3/S2=0.3987和S2/S1=0.4801,与实验值吻合得非常好。With the molecular dynamics simulation and a newly metho d for the Raman spectra calculation,we studied the changes of micro - structural and Raman spectral properties of CaSiO 3 under the quenching process from high - temperature melt down to the room - temperature glass.In the structural properties,the Si - O bond is shortened fol - lowing with the decrease of temperature,and the shortening degree of Si - O b bond is obviously greater than that of Si - O nb bond.Meanwhile,the variation of molar fractions of Si - O b and Si - O nb bonds indicated that the decrease of temperature reduced the disorder degree of the system.With the decrease of temperature,the characteristic bands of five kinds of tetrahedral units in the partial Raman spectra shifted to the high fre quency direct,and a linear relation was found between the frequency and temperat ure.The calculated results also gave the strong conclusion that the temperature has no effect on the Raman scattering coefficients.Finally,two ratios of Raman s cattering coefficients were obtained as follow:S 3 /S 2 =0.3987and S 2 /S 1 =0.4801,which agreed very well with the corre - sponding experimental values.

关 键 词：CaSiO3 熔体 玻璃 拉曼光谱性质 微观结构 计算机模拟 势函数 

分 类 号：TQ171.1[化学工程—玻璃工业]