LiCl玻璃急冷过程的分子动力学计算机模拟研究

用分子动力学方法对LiCl玻璃的急冷过程进行了计算机模拟。计算了急冷过程中各温度模拟体系的径向分布函数、配位数和Li⁺,Cl^-的自扩散系数。对模拟体系的键角进行了统计。讨论了不同温度下系统中微观空孔的分布。计算和分析清楚地表明模拟系统的玻璃态转变温度为498—298K。 关键词：

MOLECULAR DYNAMICS SIMULATIONS OF SUPERCOOLED LITHIUM CHLORIDE GLASS

Using the Tosi-Fumi pair potential, we have performed simulations of the cooling of molten salt, lithium chloride, at the rate about 5×10¹² Ks^-1 to study the glass transition and the structural and dynamic properties of the simulated supercooled liquid. It can be seen from our calculation that over the range from 498K to 298K, the peak of the radial distribution function is split into two subpeaks, the self-diffusion cofficient decrease rapidly and the distribution of bond angle has a high peak. So the simulated glass transition temperature should occur ac this range. At 298K the first coordination number of Li⁺ or Cl^- calculated from the cumulative coordination number curve N(r) is about 4. The simulation indicates the existence of microscopic holes in melt and glass. The relationship between the temperature and the number of holes is discussed.