June 11, 2007
Journal Article

CB7-: Experimental and Theoretical Evidence Against Hypercoordinated Planar Carbon

Abstract

The B82– cluster was previously shown to possess a planar molecular wheel structure with a heptacoordinated boron. Substitution of one B– by C in B82– is expected to yield a closed shell CB7– molecular wheel, which has been produced experimentally in a cluster beam and probed by photoelectron spectroscopy. Ab initio calculations show that the CB7– cluster possesses an extremely stable planar C2v structure, in which the C atom substitutes a B– atom at the edge of the B82– molecular wheel, whereas the D7h structure with a heptacoordinated C is a high-lying isomer 63.2 kcal/mol (CCSD(T)/6-311+G(2df)//CCSD(T)/6-311+G*) above the global minimum. The combined experimental and ab initio study demonstrates that a heptacoordinated planar carbon in CB7– is extremely unfavorable and is not a viable candidate for experimental realization of hypercoordinated planar carbon molecules.

Revised: April 7, 2011 | Published: June 11, 2007

Citation

Wang L., W. Huang, B.B. Averkiev, A.I. Boldyrev, and L.S. Wang. 2007. CB7-: Experimental and Theoretical Evidence Against Hypercoordinated Planar Carbon. Angewandte Chemie International Edition 46, no. 24:4550-4553. PNNL-SA-54880.