(昆明理工大學(xué) 冶金系， 昆明 650093)
摘 要: 使用BornMayerHuggins(BMH)型勢(shì)函數(shù)，用分子動(dòng)力學(xué)(MD)方法模擬計(jì)算了(NaF)x(AlF3)1-x (x=0.8, 0.75, 0.67, 0.5) 熔鹽體系在1 323 K時(shí)的結(jié)構(gòu)，得到了徑向分布函數(shù)、 FAlF鍵角分布等結(jié)構(gòu)信息，其中各熔體的FAlF鍵角分布呈現(xiàn)相似的特征，在80 °～90 °之間和160 °～170 °之間出現(xiàn)峰值。統(tǒng)計(jì)了由平衡構(gòu)像所得到的熔體中AlF的配位情況，結(jié)果證實(shí)在所得勢(shì)函數(shù)作用下，熔體中主要基團(tuán)形式是AlF3-6八面體， 其中橋氟在結(jié)構(gòu)形成中起很大作用， NaAlF4熔體中的鋁氟八面體通過(guò)氟橋連接成較大的集團(tuán)或空間網(wǎng)絡(luò)。
關(guān)鍵字: NaFAlF3； 熔鹽； 分子動(dòng)力學(xué)
（Department of Metallurgy, Kunming University of Science and Technology，Kunming 650093, P.R.China）
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 FAlF bond angle distributions for the simulated melts were calculated. It was shown that the characters of the FAlF 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 AlF 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.
Key words: NaFAlF3； molten salts； molecular dynamics
