Cu_nNi(n=2-13)团簇基态结构和电子特性的密度泛函研究  

Density functional investigation on geometric and electronic properties of Cu_nNi(n=2-13)clusters

作　　者：冯翠菊[1] 

机构地区：[1]华北科技学院基础部,北京101601

出　　处：《分子科学学报》2014年第2期124-130,共7页Journal of Molecular Science

基　　金：中央高校基本科研业务费(JCB2013B09)

摘　　要：基于第一性原理,利用密度泛函理论中广义梯度近似(GGA)对团簇Cun-1Ni和Cun(n=3-14)进行了结构优化和能量计算,结果表明,单质Cu团簇不是以密实结构而是以类平面结构生长,但Ni的掺杂使得Cu团簇结构以二十面体为基础生长并且增加了团簇的稳定性;团簇结合能的二阶差分计算表明Cu3Ni,Cu7Ni和Cu9Ni结构最为稳定;在团簇的最稳定结构中Ni原子趋于占据团簇的中心位置和更多的Cu原子形成化学键;位于表面的Cu原子成为Mülliken电荷的接受体而带负电性,这也可能是Ni掺杂Cu合金耐腐蚀性增强的原因之一;Ni的掺杂使原来没有磁性的铜团簇显示了磁性且总自旋磁矩表现明显的奇偶振荡,为1或2μB,与团簇的尺寸无关.The configurations and electronic properties of Cun-1 Ni and pure Cu. （n= 3-14） clusters have been calculated in the framework of all-electron density-function theory. On doping one Ni atom into the pure Cun clusters, the ground-state structures and the binding energy of the mixed clusters have changed. The CunNi clusters grow in an icosahedral pattern and doping of one Ni atom increases the stability of pure Cu. clusters. The Ni atom prefers to have maximum number of neighboring Cu atom and gradually falls into the interior of the Cu framework as the number of Cu atom increases from 2 to 13. The results show that the Cu3Ni, CuTNi and CugNi are more stable. In the Ni-doped copper clus- ters, Ni atom exhibits positive charge and donates electron to copper atoms. The presence of a doping atom like Ni atom can affect the chemical activity of the whole copper clusters including corrosion-re- sistant properties. The total spin of Cun-1 Ni clusters displays an odd-even oscillation, which are 1 μB and 2 μB.

关 键 词：密度泛函理论 CuNi团簇 最低能量结构 

分 类 号：O604[理学—化学]