Abstract:

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.