ELECTRON COUNTING CONTINUES TO ADD UP

Abstract

ANEW ELECTRON-COUNTING RULE derived from Wade's rule for predicting the structure and bonding requirements of cagetype compounds has been devised by chemistry professor Eluvathingal D. Jemmis and coworkers at the University of Hyderabad in India \J. Am. Chem. Soc, 123, 4313 (2001)]. The rule is expected to be a useful extension ofWade's rule to cover condensed polyhedral boranes and the many possible products created by merging boranes and metallocenes into single macromolecules. In a subsequent paper in the same issue ofJACS (page 4324) Jemmis and postdoctoral researcher Musiri M. Balakrishnarajan use the new rule to describe the electronic requirements of â-rhombohedral boron, a 105-atom allotrope containing boron polyhedra building blocks. The goal of the work is to determine missing links between polyhedral boranes and complex boron allotropes, similar to the structural and bonding connections between benzene, condensed aromatic systems, and graphite. Chemists have used electron-counting rules for man...