【摘要】 用分子动力学方法研究了不同大小的Cu原子团簇 (Cu13 ,Cu3 8,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 (Cu3 8,Cu55)则不存在这种现象更多还原

【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.更多还原