第Ⅴ主族双金属铋掺杂硼团簇Bi_(2)B_(n)^(-)(n=10,11)的理论研究

Theoretical study of bismuth-doped boron clusters Bi_(2)B_(n)^(-)(n=10,11)of bimetallic bismuth in the Vth main group

利用量子化学理论计算对掺杂Bi的硼团簇Bi_(2)B_(n)^(-)(n=10,11)进行了研究,结果显示Bi_(2)B_(10)^(-)的全局最稳定结构是由一个B_(10)环和两个Bi原子结合在其边缘组成的完美平面,具有双重芳香性。Bi_(2)B_(11)^(-)的全局最稳定结构是半三明治结构,是由一个Bi原子在B_(11)环边缘的一侧与B_(11)环结合,另一个Bi原子插入B_(11)环的另一侧与其配位,具有双重反芳香性。成键分析表明Bi原子通过其3个6p轨道与平面硼原子具有共价键作用,形成两个Bi-Bσ键,分别为6p_(x)和6p_(y)轨道,而6p_(z)轨道参与形成离域π键。因此,B_(n)环(n=10,11)和主族双金属Bi掺杂后表现出不一样的性质,通过对Bi_(2)B_(n)^(-)进行几何构型、电子构型和光电子能谱模拟分析,相较于其他构型,Bi_(2)B_(n)^(-)更易于形成平面结构和半三明治式结构。

The study used quantum chemical theoretical calculations to study a series of Bi doped boron clusters Bi_(2)B_(n)^(-)(n=10,11).The results show that the globally most stable structure of Bi_(2)B_(10)^(-) is a perfect plane composed of a B 10 wheel and two Bi atoms bound at its edges,exhibiting dual aromaticity.The global minimum of Bi_(2)B_(11)^(-) is a semi-sandwich structure,which consists of a Bi atom bound to the B_(11) ring on one side,and another Bi inserted on the other side of the B_(11) ring with its coordination thus possessing double anti-aromaticity.The bonding analysis showed that the Bi atom interacted with the planar boron atom through its three 6p orbitals by covalent bonds to form two Bi-Bσ bonds,which were 6p_(x) and 6p_(y) orbitals,respectively,while the 6p_(z) orbital participated in the formation of the delocalizedπbond.Therefore,B_(n) ring with larger size(n=10,11)and the main group bimetallic Bi show different properties after doping,and the geometrical configuration,electronic configuration and Photoelectron Spectroscopy of Bi_(2)B_(n)^(-) show that it is more likely to form planar and semi-sandwich structures as compared to the other configurations of Bi_(2)B_(n)^(-).