Pan Fu-Xing, Xu Cong-Qiao, Li Lei-Jiao, Min Xue, Wang Jian-Qiang, Li Jun, Zhai Hua-Jin, Sun Zhong-Ming
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
Dalton Trans. 2016 Mar 7;45(9):3874-9. doi: 10.1039/c6dt00028b. Epub 2016 Feb 1.
We describe here the synthesis and characterization of a ternary cluster compound As3Nb(As3Sn3) (1), in which a niobium(v) atom is coordinated by an As3(3-) triangle and a bowl-type As3Sn3(5-) ligand. Cluster 1 was synthesized by dissolving K8NbSnAs5 (2) in the presence of [2.2.2]crypt in ethylenediamine solution, filtered and layered with toluene, then crystallized in the form of [K([2.2.2]crypt)]3[As3Nb(As3Sn3)]·en·tol. The flower-vase shaped compound 1 features a new structure type, rather different from the known Zintl phases. The stability and bonding of 1 are elucidated via extensive bonding analyses. The Sn3 ring is found to have σ-aromaticity featuring a delocalized Sn-Sn-Sn σ bond. Electronic structure calculations confirm the Nb(v) oxidation state and weak Nb-Sn and Sn-Sn bonding, in addition to the normal Nb-As and As-As bonds.
我们在此描述一种三元簇合物As3Nb(As3Sn3)（1）的合成与表征，其中一个铌（V）原子由一个As3(3-)三角形和一个碗状As3Sn3(5-)配体配位。簇合物1是通过在乙二胺溶液中于[2.2.2]穴醚存在下溶解K8NbSnAs5（2），过滤并用甲苯分层，然后以[K([2.2.2]穴醚)]3[As3Nb(As3Sn3)]·en·tol的形式结晶而合成的。花瓶状化合物1具有一种新的结构类型，与已知的津特耳相有很大不同。通过广泛的键合分析阐明了1的稳定性和键合情况。发现Sn3环具有σ芳香性，其特征是存在离域的Sn - Sn - Sn σ键。电子结构计算证实了铌（V）的氧化态以及除了正常的Nb - As和As - As键之外的弱Nb - Sn和Sn - Sn键。
