NaF-AlF3系熔盐结构的分子动力学计算
来源期刊：中国有色金属学报2000年第6期
论文作者：侯怀宇 谢刚 陈书荣 张雄飞
文章页码：914 - 918
关键词：NaF-AlF3； 熔盐； 分子动力学
Key words：NaF-AlF3； molten salts； molecular dynamics
摘 要：使用Born-Mayer-Huggins(BMH)型势函数，用分子动力学(MD)方法模拟计算了(NaF)x(AlF3)1-x (x=0.8, 0.75, 0.67, 0.5) 熔盐体系在1 323 K时的结构，得到了径向分布函数、 F-AlF键角分布等结构信息，其中各熔体的F-Al-F键角分布呈现相似的特征，在80 °～90 °之间和160 °～170 °之间出现峰值。统计了由平衡构像所得到的熔体中Al-F的配位情况，结果证实在所得势函数作用下，熔体中主要基团形式是AlF3-6八面体， 其中桥氟在结构形成中起很大作用， NaAlF4熔体中的铝氟八面体通过氟桥连接成较大的集团或空间网络。
Abstract: The structure of the molten system (NaF)x (AlF3)1-x (x=0.8, 0.75, 0.67,0.5) at 1 323 K has been calculated by MD method using the BornMayerHuggins(BMH) type potential function. The radial distribution functions and F-Al-F bond angle distributions for the simulated melts were calculated. It was shown that the characters of the F-Al-F bond angle distributions in all the simulated melts arequite similar, the peaks occur at the regions of 80 °～90 ° and 60 °～170 °. Further more, the coordination for Al-F was analyzed from the configuration simulated. The obtained results suggested that the Al3+ and F- connect themselves to form AlF3-6 octahedra in all the simulated melts. It was observed that fluorine bridges play an important role in the structures of the melts. In the NaAlF4 melt,the octafluoroaluminate anions are linked each other by fluorine bridges and a large group or network is then formed.
