Confirmed by X‐ray Crystallography: The B⋅B One‐Electron σ Bond

Abstract

Is one electron sufficient to bring about significant s bonding between two atoms? The chemists view on the chemical bond is usually tied to the concept of shared electron pairs, and not too much experimental evidence exists to challenge this firm belief. Whilst species with the unusual one-electron s-bonding motif between homonuclear atoms have so far been identified mainly by spectroscopic evidence, we present herein the first crystallographic characterization, augmented by a detailed quantum-chemical validation, for a radical anion featuring a B·B one-electron-two-center s bond.

One-electron bonds in copper–aluminum and copper–gallium complexes

“…1b ). 21 Examples of 2c/1e σ-bonds between the heavier Group 13 congeners are even more lacking because of the greater propensity for their unpaired spins to couple, forming larger more stable clusters. 8 To our knowledge, there are only three structurally characterized examples of odd-electron bonds for the heavy Group 13 atoms, 22 and these examples are all homonuclear π-radicals ( Fig.…”