B14: An all-boron fullerene

2012 Journal of Chemical Physics  
Experiments revealed that small boron cluster anions and cations are (quasi-)planar. For neutral boron cluster, (quasi-)planar motifs are also suggested to be global minimum by many theoretical studies, and a structural transformation from quasi-planar to double-ring tubular structures occurs at B 20 . However, a missing opportunity is found for neutral B 14 , which is a flat cage and more stable than the previous quasi-planar one by high level ab initio calculations. The B 14 cage has a large
more » ... OMO-LUMO gap (2.69 eV), and NICS values reveal that it is even more aromatic than the known most aromatic quasi-planar B 12 and double-ring B 20 , which indicates a close-shell electronic structure. Chemical bonding analysis given by AdNDP reveals that the B 14 cage is an all-boron fullerene with 18 delocalized σ -electrons following the 2(n+1) 2 rule of spherical aromaticity. The geometry and bonding features of the B 14 cage are unique denying conversional thinking.
doi:10.1063/1.3692183 pmid:22423832 fatcat:kvuy3o346zgvxifine6mirvctu