Sun Jiao, Lu Wen-Cai, Zhao Li-Zhen, Zhang Wei, Li Ze-Sheng, Sun Chia-Chung
State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130021, People's Republic of China.
J Phys Chem A. 2007 May 24;111(20):4378-83. doi: 10.1021/jp068591o. Epub 2007 Apr 21.
The structures, binding energies, and electronic properties for Al7X, Al7X-, Al13X-, Al13X2-, and Al13X12- (X = F, Cl, Br) were studied at the B3LYP/6-311+G(2d,p) level. Among the systems studied, Al7 and Al13 clusters in Al7X and Al13X- reveal alkali-like and halogen-like superatom characters, respectively. Al7 can bind with one halogen atom to form a salt-like compound as Al7+delta-X-delta. Al13- can combine with one halogen atom to form a diatomic halogen anion Al13X-. However, when adding more halogens, the superatom structure would be destroyed, resulting in low-symmetry compounds with the center Al atom moving toward the cluster surface. The structures of Al13X1,2,12- (X = F, Cl, Br) are similar to those of X = I; however, their binding energies and electron structures are much different. In addition, the analyses of the calculated NBO charges show that Cl and Br have similar properties, but much different from F, when interacting with the Al clusters. The Al-Cl and Al-Br bonds have more covalent character in Al7X and Al13X2,12-, in contrast to the corresponding Al-F bond, which has prominent ionic character.
在B3LYP/6-311+G(2d,p)水平下研究了Al7X、Al7X-、Al13X-、Al13X2-和Al13X12-（X = F、Cl、Br）的结构、结合能和电子性质。在所研究的体系中，Al7X中的Al7和Al13X-中的Al13簇分别呈现出类碱和类卤超原子特征。Al7可与一个卤原子结合形成盐类化合物Al7+δ-X-δ。Al13-可与一个卤原子结合形成双原子卤阴离子Al13X-。然而，当添加更多卤素时，超原子结构会被破坏，导致中心Al原子向簇表面移动的低对称化合物。Al13X1,2,12-（X = F、Cl、Br）的结构与X = I时的结构相似；然而，它们的结合能和电子结构有很大差异。此外，对计算得到的自然键轨道（NBO）电荷的分析表明，Cl和Br在与Al簇相互作用时具有相似的性质，但与F有很大不同。与具有显著离子特征的相应Al-F键相比，Al-Cl和Al-Br键在Al7X和Al13X2,12-中具有更多的共价特征。
