利用双晶格势进行硅的分子动力学模拟及其有效性  

Double Lattice Potential for Molecular Dynamics Simulation of Silicon with Demonstrated Validity

作　　者：魏崇阳 张辉[1] 刘仲武[1] 钟喜春[1] 焦东玲[1] 邱万奇[1] 余红雅[1] WEI Chongyang;ZHANG Hui;LIU Zhongwu;ZHONG Xichun;JIAO Dongling;QIU Wanqi;YU Hongya(School of Materials Science and Engineering,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学材料科学与工程学院,广东广州510640

出　　处：《材料科学与工程学报》2022年第6期948-955,共8页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(11204087,52071143)。

摘　　要：为了在分子动力学模拟中获得硅的金刚石结构,本研究提出了双晶格(DL)势的概念。双晶格势由两个描述面心立方晶格和一个描述两晶格间原子相互作用的势构成。该双晶格势用于Si晶体结构分子动力学模拟,并与Tersoff势、Stillinger-Weber(SW)势、原子间作用(EDI)势、电荷优化多体(COMB)势和修饰嵌入原子(MEAM)势的计算结果进行了对比。采用计算原子之间的距离及原子与其最近邻原子之间的角度的分布函数来识别模拟Si系统的晶体结构,并与理想的Si晶体进行比较。基于上述作用势通过分子动力学模拟计算了晶格常数,结晶温度和弹性常数。结果表明,只有DL势才能获得金刚石结构,模拟结果弹性常数大约比实验数据大13%,晶格常数约大4%。显示出DL势对Si晶体结构的分子动力学模拟的有效性。To reproduce the diamond structure of silicon,double lattice(DL)potential constructed from two interatomic potentials for face centered cubic(fcc)lattice,is proposed for molecular dynamics(MD)simulations.For the validity test of MD simulation,Tersoff potential,Stillinger and Weber(SW)potential,environment-dependent interatomic(EDI)potential,charge optimized many-body(COMB)potential,and modified embedded-atom(MEAM)potential have been also employed for comparison.The crystal lattice of simulated silicon system is identified by calculating the distribution functions of the distances between the atoms and the angles between the lines linking an atom with its nearest neighbor.The results are also compared with the perfect silicon crystal.The lattice constant,the crystallization temperature,and elastic constants have been calculated from MD simulations using above potentials.The results show that only the DL potential can give diamond lattice,and the simulation results of elastic constant and lattice constant are only 13%and 4%larger than the experimental data,respectively.It shows the validity of DL potential for molecular dynamics simulation of Si crystal structure.

关 键 词：金刚石结构 硅原子间相互作用势 分子动力学模拟 晶格识别 

分 类 号：TB303[一般工业技术—材料科学与工程]