title: The inverted bond in [1.1.1]propellane is a charge-shift bond.
abstract: Bonded or not bonded? An ab initio valence bond study of [1.1.1]propellane shows that the two bridgehead carbons are linked by a strong and direct sigma bond that is neither classically covalent nor classically ionic, but rather a charge-shift bond, in which the covalent-ionic resonance energy plays the major role. As such, the central bond of [1.1.1]propellane closely resembles the single bond of difluorine.
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.forename: Junjing
authors.initials: J
authors.lastname: Gu
authors.forename: Jinshuai
authors.initials: J
authors.lastname: Song
authors.forename: Sason
authors.initials: S
authors.lastname: Shaik
authors.forename: Philippe C
authors.initials: PC
authors.lastname: Hiberty