Ni2Bn(n=1~10)团簇的结构与稳定性研究

Study on the Structure,Stability of Ni2Bn(n=1~10)Clusters

使用密度泛函理论下的广义梯度近似对过渡金属Ni原子掺杂硼基纳米团簇Ni2Bn(n=1~10)的几何构型、稳定性、电子性质进行了系统的研究.研究结果表明:当n≤5时,只有Ni2B3团簇为立体结构,其余团簇的最低能量异构体都是平面结构.当n=6~10时,它们的最稳定结构均为三维(3D)立体结构.根据平均结合能和二阶差分能量值分析,Ni2B7团簇非常稳定,被确定为幻数团簇.垂直电离势(VIP)、电子亲合势(VEA)和化学硬度(η)的分析进一步表明Ni2B7具有较高的化学稳定性.除Ni2B6的自旋磁矩为2μB外,其他团簇,当n偶数时,自旋磁矩为0μB,n为奇数时自旋磁矩为1μB.

The geometries,stabilities and electronic properties of Ni2Bn(n=1~10)clusters were investigated by using the generalized gradient approximation method under the density functional theory framework.The results showed that when n≤5,only the Ni2B3 cluster has a 3D structure,while the lowest energy isomers of the remaining clusters are all planar structures.When n=6~10,the global minimum structures of Ni2Bn clusters are all in three-dimensional structures.According to the analysis of average binding energy and second-order differential energy,we found that Ni2B7 has higher stability compared to adjacent clusters.So Ni2B7 wasconfirmed as a magic cluster.The analysis of VIP,VEA and η further showed that the Ni2B7 has a stable electronic structure.the spin magnetic moment of Ni2Bn is 0μB for even n,and 1μB for odd n except Ni2B6,which has a spin magnetic moment of 2μB.