熔融BaB_2O_4急冷玻璃态光谱性质的分子动力学模拟  

A Molecular Dynamics Study of Raman Spectra for BaB 2O 4 Glass

作　　者：陈柳[1] 程兆年[1] 汤正诠[2] 唐鼎元[3] 

机构地区：[1]中国科学院上海冶金研究所 [2]上海大学理学院 [3]中国科学院福建物质结构研究所

出　　处：《人工晶体学报》1999年第2期126-134,共9页Journal of Synthetic Crystals

基　　金：国家自然科学基金

摘　　要：实验测定和分子动力学模拟研究了熔融ＢａＢ２Ｏ４急冷玻璃态结构的Ｒａｍａｎ光谱。在分子动力学模拟产生的瞬态位移和速度基础上，发展了各种相关函数及其Ｆｏｕｒｉｅｒ变换和有关动力学性质的计算程序。计算得到了βＢａＢ２Ｏ４晶态和玻璃态的Ｂ—Ｏ键长自相关函数和Ｏ原子相对位移互相关函数，及其Ｆｏｕｒｉｅｒ变换得出的Ｒａｍａｎ光谱。实验与模拟结果表明，在分子动力学模拟中调节势参数ｋ＝０．５８时，计算的晶体Ｒａｍａｎ谱主峰在６８３ｃｍ－１，玻璃态Ｒａｍａｎ谱中ＢＯ３的主峰在７６８ｃｍ－１，ＢＯ４的主峰在５９０ｃｍ－１，与实验基本相符。模拟结果表明，玻璃体中存在大量ＢＯ３基团及少量ＢＯ４基团，虽然模拟体系中很少存在Ｂ３Ｏ６环。The Raman spectra properties of quenched BaB 2O 4 glass have been studied by means of the experimental measurement and the molecular dynamics simulation.Based on the instantaneous configurations and displacements given by the simulation,the calculation programs of some correlation functions,Fourier transmissions functions and related dynamics properties have been developed.The autocorrelation function of the B O bond lengths,the intercorrelation function of the relative displacements between O atoms and the Raman spectra calculated from the Fourier transmission have been obtained.The simulations results showed that by using an adjustment parameter k =0.58,the simulated main Raman peak 683cm -1 in crystal,the main peak 768cm -1 of BO 3 unit in glass,and the main peak 590cm -1 of BO 4 unit in glass,are in good agreement with the experimental results.The simulation results indicated that an experimental Raman spectra could be roughly reproduced from the configuration simulated with a plenty of BO 3 units and a few BO 4 units,even though there are few B 3O 6 rings in the configuration .

关 键 词：分子动力学 模拟 光谱 硼酸钡晶体 玻璃态 

分 类 号：O795[理学—晶体学] O743.3