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CHEMISTS in Utah have discovered carbon-to-carbon bonds twice the length of
any seen before. Joel Miller at the University of Utah in Salt Lake City found
the long bonds in tetracyanoethylene (TCNE) and also in eight related compounds.
Measuring 0.28 to 0.31 nanometres, the links were double the length of the bonds
in diamond— usually considered the limit. In the online journal
Angewandte Chemie, Miller described how his team discovered the bond in a
TCNE dimer—two molecules joined together. “There’s this special
interaction between the central atoms,” he said. “It’s two electrons spread over
four carbon atoms.”