熔融LiCL中的Voronoi多面体

分子动力学计算表明,在熔融LiCl中存在与组分离子尺寸相当的微观空孔。微观空孔的分布规律对理解系统的扩散系数、电导系数、粘度、压缩率和热膨胀系数等都有重要意义,它们与自由体积模型中的自由体积也有密切的关系。

VORONOI POLYHEDRON IN LiCI MELT

The results of the moleoular dynanmics simulation of LiCl melt indicate the existence of microscopic holes in molten salt. Some holes are of size comparable to that of Li~+ ion and Cl~- ion. In order to describe the holes in melt better a modified Bernal model has been proposed, in which the centre of the hole with diameter equal or larger than that of Li~+ or Cl~- ion is considered as centre of "virtue" particle, and takes part in the construction of Voronoi polyhedron. It can be seen from our calculation: 1, the Voronoi polyhedron in LiCl melt is more complex than that of the simple liquid; 2, the Voronoi polyhedron of Cl~- ion is more complex than that of Li~+ ion; 3, the face of the Voronoi polyhedron can be observed clearly in the Voronoi polyhedron of Cl~- ion; 4, the Voronoi polyhedron of hole with the diameter near equal to Li~+ ion is more complex than that of Li~+ ion, while the Voronoi polyhedron of the hole with the diameter equalto that of Cl~- ion has the similar geomitrical behaviour as that of Cl~- ion. The reason of above phenomena is discussed briefly.