Boron cluster forms unique ring system

Clusters of nineteen boron atoms gather together in a ring structure unlike any other seen, with two planar -bonded aromatic systems nestled inside one another.   

Lai-Sheng Wang at Brown University and Alexander Boldyrev at Utah State University in the US made the discovery: 'I was really excited when my postdoc, Wei Huang, first showed it to me,' Wang told Chemistry World. 'It's so beautiful, so circular.' 

The US chemists found that the lowest energy form of B₁₉^- boasts a pentagonal six-atom group sharing two -electrons, surrounded by thirteen boron atoms sharing ten electrons. Although concentric -systems have been seen in organic molecules, none have exactly this electronic configuration.  More...

http://www.rsc.org/chemistryworld/News/2010/January/24011001.asp