MOLECULAR DYNAMICS STUDY OF STRUCTURE IN MOLTEN SALT SOLUTION NaF-CaF_2
NaF—CaF2熔盐溶液结构的分子动力学模拟研究

The molten NaF-CaF_2 system has been studied by molecular dynamicssimulation. The pair correlation functions between cations and anionsand the bond angle dis-tributions of cation and anion triplets have beenobtained. The bridging and complexing in thesystem are discussedbased on the pair correlation functions and bond angle distributions.Theresults simulated show that the F~- ions around Ca~(2+) ion do not form tetrahedroncoordination, so that some of small complexing clusters such as CaF_4~(2-) are hardly found. Apossible structure of F~-; ions around Ca~(2+) ions is that three Ca~(2+) ions consistute an equilat-eral triangle through three Ca-F-Ca bridges and two F~- ions are located over and under thecenter of the right triangle, respectively. Meanwhile, on the outside of the triangle, everyCa~(2+) ion has another two F~- ions as its neighbor.