原子与分子物理学报, 2003, 20 (2): 229, 网络出版: 2006-05-19  

小Cu团簇熔化过程中的预熔化行为

The premelting behavior of small copper clusters in the melting process
作者单位
1 曲阜师范大学物理系,山东,曲阜,273165
2 南京大学物理系,江苏,南京,210093
摘要
用分子动力学方法研究了不同大小的Cu原子团簇(Cu13,Cu38,Cu55)的熔化行为.发现对于小的团簇(Cu13),在接近熔化温度时,其内部存在着一种特殊的预熔化行为:内部原子的相对扭转,这种扭转使得Cu13团簇在保持基态结构不变的同时,其内部的原子又具有一定的流动性,对于较大的团簇(Cu38,Cu55)则不存在这种现象.
Abstract
The melting behavior of Atomic clusters, Cu 13 , Cu 38 , Cu 55 was studied by molecular dynamics (MD). It is found that the melting point of Cu 13 defined by the heat capacity line is much higher than that defined by the root mean square (rms) inter atomic distance fluctuation, whereas such difference doesn't appear in the melting process of Cu 38 and Cu 55 . Further research reveals that such phenomenon is caused by a special premelting mechanism: the collective rotation of the small cluster in the melting process.
参考文献

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詹仪, 丁峰, 李新乡, 王广厚. 小Cu团簇熔化过程中的预熔化行为[J]. 原子与分子物理学报, 2003, 20(2): 229. 詹仪, 丁峰, 李新乡, 王广厚. The premelting behavior of small copper clusters in the melting process[J]. Journal of Atomic and Molecular Physics, 2003, 20(2): 229.

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