中文摘要：

采用分子动力学方法和镶嵌原子势，模拟了500个Ni原子（简称Ni500）组成的纳米团簇的等温晶化过程．通过对纳米Ni团簇的动力学行为和微观结构演变的研究，发现Nisoo在高温时是一步晶化的，在低温时则呈现出多步晶化的特征，在多步晶化的过程中，团簇结构会陷入多个亚稳态结构，经过原子重排，进入能量更低的亚稳态，最后完成晶化．在多步晶化过程中，原子的位置重排是通过协同跳跃运动实现的，其协同运动方式不但有常见的线型协同运动，也有多个原子的集体平移运动等其他形式．

英文摘要：

Molecular dynamics simulations are performed on nano clusters with 500 nickle atoms （Nis0o） to determine the structure and dynamics in the isothermal crystallization using embed atom model potentials. Through the study of nano Ni cluster dynamic behavior, we find that multi-step crystallization process of Ni50o is at temperatures far below the melting temperature （Tin）, whereas one-step crystallization process is at the temperatures just below Tin. Multi metastable states are observed before Nis0o becomes fully crystallized in multi-step crystallization process. We find that atom rearrangements take not only string-like cooperative motion manner but also other collective motion manner.