熔融BaB_2O_4急冷玻璃态结构和态密度的分子动力学模拟  

Structure and Density of State for BaB 2O 4 Glass: a Molecular Dynamics Study

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1期1-7,共7页Journal of Synthetic Crystals

基　　金：国家自然科学基金

摘　　要：采用分子动力学模拟方法研究了熔融ＢａＢ２Ｏ４急冷玻璃结构。模拟得到玻璃体的径向分布函数、配位数与熔体的实验结果相近。模拟结果表明，熔态和急冷玻璃态中存在大量ＢＯ３基团及少量ＢＯ４基团，而很少存在Ｂ３Ｏ６环。在分子动力学模拟产生的各瞬态构型基础上，通过正态模式分析方法，研究了Ｈｅｓｉａｎ矩阵元和Ｈｅｓｉａｎ矩阵本征值的计算方法，并统计得到了ＢＢＯ玻璃体静态态密度。在分子动力学模拟产生的各瞬时速度基础上，发展了速度自相关函数及其Ｆｏｕｒｉｅｒ变换程序，并计算得到玻璃体的动态态密度。模拟表明，通过各瞬态构型用Ｈｅｓｉａｎ矩阵计算得到的态密度也与由速度自相关函数的快速Ｆｏｕｒｉｅｒ分析结果得到的态密度符合得很好。The structure of quenched glass from molten BaB 2O 4 has been studied by molecular dynamics simulation.The radial distributions function and coordination numbers from the simulation are closed to the experimental results reported recently.The results from the simulation showed that in the molten system and quenched glass system simulated,there are a plenty of planar BO 3 units and a few tetrahedral BO 4 units while few B 3O 6 rings.Based on the instantaneous configurations generated by the simulation,the calculation method of Hessian matrix and eigenvalues has been suggested by using normal mode analysis and the density of static state of BaB 2O 4 glass has been obtained by statistical averaging.Based on the instantaneous velocities given by the simulation,the programs for calculating velocity autocorrelation function and its Fourier transmission have been developed and the density of dynamic state has been given out.The results calculated showed that the density of state obtained from Hessian matrix is in good agreement with that from the velocity autocorrerlation function.

关 键 词：分子动力学模拟 偏硼酸钡晶体 态密度 玻璃态 

分 类 号：O795[理学—晶体学] O614.233