温度对金属纳米线势能分布的影响

采用三维分子动力学模拟方法,以面心立方金属银为研究对象,基于Finnis-Sinclair型嵌入原子法(EAM)多体势,模拟研究了纳米线势能分布特征在常温下及其在不同温度直到熔化过程中的变化,给出了常温及不同温度银纳米线势能分布比例和势能分布函数.结果表明:常温下,纳米线高势能原子比例随纳米线横截面尺寸的减小而增大,势能分布函数曲线各峰位几乎与纳米线横截面尺寸无关;纳米线熔化前的势能分布函数曲线具有多个波峰,随着温度增加,峰数减少且峰位右移;熔化后,多峰特征消失,只有一个宽化的峰.

Effect of the temperature on potential energy distribution of metal nanowires

A three-dimensional molecular dynamics simulation method and Finnis-Sinclair embedded atom potential were utilized to study the potential energy distribution characteristic of an fcc Ag nanowires at room temperature and its changes during heating,by which we get the ratio and function of the potential energy distribution of Ag nanowires at different temperatures.The results show that,at room temperature,the high potential energy atomic ratio increases with decreasing of the size of the nanowire,and positions of the curves peaks are no related to its sizes.Multi-peaks can be seen in the potential energy distribution curve of the atoms in the nanowires before melting,the numbers of the peak decreases and moves to right with the increasing of the temperature.However,the multi-peak potential energy distribution curve degenerated to the broadened single-peak curve as the nanowire is melted.