COMPUTER SIMULATION OF STRUCTURE OF MOLTEN DyF3-BaF2-LiF SYSTEM BY MONTE CARLO METHOD
(Shanghai Institute of Metallurgy, Chinese Academy of Sciences, Shanghai200050)
Abstract: The structure of molten DyF3-BaF2-LiF system has been computer-simulated by Monte Carlo method. The radial distribution functions (RDFs), the local structure as well as the energy distribution have been obtained. The study indicates that F- ions distribute closely around Dy3+ ions and mainly form octahedral complex ions like DyF63-. There exist some “free” Li+ ions in the molten system, which have the highest potential energy and are current-carrying ions in the electrolytic process. F-ions may be classified into three types:“terminal fluoride”,“free fluoride”and“bridge fluoride”, which have different behaviours and potentialenergies. Some complex ions like DyFm3-m clusters are connected to one another by“fluoride-bridge”, forming more complicated ionic clusters like Fm-Dy-F-Dy-Fn or Fm-Dy < FF>Dy-Fn. As compared with
molten DyF3-LiF system, the octahedral complex ions like DyF63- seem closer and in better order than the binary system because of the addition of BaF2.
molten DyF3-LiF system, the octahedral complex ions like DyF63- seem closer and in better order than the binary system because of the addition of BaF2.
Key words: rare-earth fluoride molten salt computer simulation Monte Carlo method local structure