RbCl键取向序的分子动力学模拟

A STUDY OF BOND ORIENTATION ORDER IN RUBIDIUM CHLORIDE BY MOLECULAR DYNAMIC SIMULATION

进行T=80,300,1023K晶态和熔融态RbCI的分子动力学模拟,并对模拟结果进行了键序参数分析.模拟表明,采用Fumi-Tosi形式的两体有效势与Dixon和Sangster给出的势参数,可很好地重复EXAFS和中子散射实验结果.熔融RbCI中的键取向序,可很好地用两结构模型来描述,简单立方局部结构约占65%,正四面体占35%.通过两结构模型对径向分布函数非对称展宽、配位数、键角分布和粘度作了讨论.

The molecular dynamic simulations on the crystalline phase and molten phase of rubidium chloride have been carried out at the temperature T- 80, 300 and 1023K, and the result from the simulations have been analysed with the bond order parameter method. Adopted the Fumi-Tosi pair potential and the potential parameters given by Dixon and Sangster, the simulation results are coincident very well with the experimental result given by EXAFS and neutron scattering. The bond orientation order of molten rubidium chloride could be satistactorily described by two-structure linear combination model with 65% local SC and 35% local TE-TR structures. By using two-structure linear combination model, the asymmetric broadening of RDF, the coordination number, the bond angle distribution and the viscosity of chlorides have also been discussed.