银纳米杆中原子能量分布特征的分子动力学研究

采用分子动力学方法和嵌入原子法（EAM）多体势函数，模拟研究了银纳米杆能量分布特征在不同温度直到熔化过程中的变化。结果显示：纳米杆中原子的势能分布曲线呈现多个分立的峰；随着温度的变化，分布曲线各个峰的位置保持不变，但峰高和峰宽明显变化；纳米杆熔化后这种能量分布特征完全消失，只有一个宽化的峰。模拟结果分析表明：纳米杆中原子势能分布曲线中每个峰对应于一定的最近邻原子数，纳米杆中每个原子的势能所处峰位由其最近邻原子数决定，偏离峰值程度则由其次近邻原子数决定。

Molecular dynamics study of the atomic energy distribution characteristics of Ag nanorods

The energy distribution characteristics for Ag nanorods at different temperatures(including melting)have been investigated by molecular dynamics using an embedded-atom potential.The results showed that the potential energy curves for Ag nanorods have multiple discrete peaks,which retain the same position whilst varying in width and height with temperature.The peaks collapsed to a broadened single-peak as the nanorods were melted.Analysis showed that each peak corresponds to a specific number of nearest neighbor atoms.The peak value is determined by the number of the nearest neighbor atoms,whilst the extent of deviation from the peak value is determined by the number of the next-nearest neighbor atoms.