Carbon bond that uses only one electron seen for first time

Scientists have observed a single-electron covalent bond between two carbon atoms for the first time. Researchers synthesized a molecule with a stable ‘shell’ of fused carbon rings that stretched out a carbon–carbon bond in its centre. The pull makes it susceptible to losing one electron in an oxidation reaction, leaving the elusive one-electron bond. With the new finding, the team hopes to better understand what defines a chemical bond in the first place.