Density functional theory study of the B6, B6+, B6−, and B62− clusters

Bare neutral, cationic, anionic, and dianionic B6 clusters have been investigated using density functional theory (DFT) method. Eight B6, five B6+, five B6−, and four B62− local minima have been obtained at the B3LYP/6-31+G(d) level of theory. Closed planar or quasi-planar six-membered ring structures (C2h and D2h) are found to be the most stable structures for all the neutral and charged B6 clusters. Highly delocalized σ bonding as well as π bonding are universal in all the cyclic planar (C2h, D2h, C2v, and C2); convex (C5v and Cs); and three-dimensional (Oh, D4h, and D2h) caged structures.