38原子Ni、Pd、Pt团簇异常熔化行为的分子动力学模拟  

Molecular dynamical simulations on the abnormal melting properties of Ni_(38)、Pd_(38) and Pt_(38) clusters

作　　者：孙学贵[1] 段海明[1] 

机构地区：[1]新疆大学物理科学与技术学院,乌鲁木齐830046

出　　处：《原子与分子物理学报》2012年第4期731-738,共8页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(10864005;11164029);新疆维吾尔自治区自然科学基金(2011211A008)

摘　　要：采用半经验的Gupta多体势结合分子动力学方法,系统的研究了Ni_38、Pd_(38)、Pt_(38)团簇的熔化特性,我们发现这3种团簇的熔化行为均有别于热熔曲线呈现一宽峰的满壳层结构的团簇的熔化行为,其热熔曲线均无明显宽峰,通过对团簇原子等价指数的分析表明出现这种异常熔化行为的主要原因是因为在团簇预熔化过程中出现了两种动力学结构(Oh与类Ih结构)之间的竞争.The melting properties of Ni38、Pd38 and Pt38 clusters are systematically investigated by molecular dynamical simulations combined with the Gupta-type many-body potential. We found that for these 38-atom clusters there are no broadening peaks in the heat capacity curve, this melting behavior is substantially different from that in the conventional melting of a cluster where the heat capacity curve exhibits a broadening peak. By analyzing the atomic equivalence indexes the origin of the abnormal melting properties can be attributed to the competition between two dynamical structures （Oh-like and Ih-like） in the process of cluster melting.

关 键 词：GUPTA势 团簇 分子动力学 熔化 

分 类 号：O469[理学—凝聚态物理] O561.1[理学—电子物理学]