Ge_nMn(n≤8)团簇的电子结构与磁性的密度泛函理论研究  

Electronic structure and magnetic properties of Ge_nMn(n≤8) clusters:the density functional calculations

作　　者：白熙[1] 吕瑾[2] 高慧[1] 杨金香[1] 

机构地区：[1]长治医学院药学系,长治046000 [2]山西师范大学化学与材料科学学院,临汾041004

出　　处：《原子与分子物理学报》2016年第3期463-469,共7页Journal of Atomic and Molecular Physics

摘　　要：采用密度泛函理论下广义梯度近似方法,对Mn掺杂Ge基半导体团簇Ge_nMn(n≤8)的结构与磁性进行了理论研究.结果表明:Ge_nMn(n≤8)的最稳定构型与相应的Ge_(n+1)团簇相似.Mn掺杂后团簇的原子平均结合能与纯锗团簇比较近似;能量二次差分表明:Ge_3Mn和Ge_5Mn团簇较相邻团簇表现出较高的稳定性;当n=1,3和6时,HMO-LUMO能隙较大,n=2时,能隙较小,说明GeMn、Ge_3Mn和Ge_6Mn具有相对较好的化学稳定性,而Ge_2Mn具有较高的化学活性.对Ge_nMn(n≤8)团簇的磁性研究发现,除Ge_8Mn的总磁矩为1μB外,其他团簇的总磁矩均为3μB,且团簇的磁性主要来源于Mn原子.The electronic structures and magnetic properties of GenMn（ n≤8）clusters have been investigated by using the density functional theory （DFT） with the generalized gradient approximation （GGA）. The most stable geometries of GenMn（ n≤8）are similar with those of Gen＋ 1 clusters. The second- order energy differences show that ： Ge3Mn and Ge6 Mn clusters have batter stabilities than the neighbor clusters. When n = 1,3 and 6, the HOMO -LUMO gaps are big, whereas that of Ge2 Mn cluster is smallest, suggesting that it has higher chemical activity than others. All the clusters exhibit 3 μB total magnetic moments except for GesMn clusters.

关 键 词：密度泛函理论 GenMn团簇 电子结构 磁性 

分 类 号：O641.121[理学—物理化学]