COMPUTERIZED SIMULATION OF STRUCTURE OF CRYOLITE MELT

The structure of molten cryolite has been investigated by computerized simulation using Monte Carlo method. The radial distribution functions and some parameters describing the local structure of 3NaF·AlF_3 melt at 1283K have been calculated. It is concluded that a part of F~- ions in AlF_6~3-moves away from Al~(3+) ions after the melting of cryolite, forming xNa~+·yF~- clusters with Na~+ ions. The removal of a part of F~- from AlF_6~(3-) makes it disintegrated into some local structures like AlF_4~- or AlF_5~(2-). Some Al~(3+) ions are connected to each other by AlF-Al bridges, forming ionic clusters like Al_2F_7~-, etc. It is also concluded that the distribution of the free space in molten cryolite is not uniform. There are more fissures and holes in xNa~+·yF~- clusters and between AlF_4~- and xNa~+·yF~- clusters.