title: Electron-deficient and polycenter bonds in the high-pressure γ-B28 phase of boron.
abstract: The peculiar bonding situation in γ boron is characterized on the basis of an experimental electron-density distribution which is obtained by multipole refinement against low-temperature single-crystal x-ray diffraction data. A topological analysis of the electron-density distribution reveals one-electron-two-center bonds connecting neighboring icosahedral B(12) clusters. A unique polar-covalent two-electron-three-center bond between a pair of atoms of an icosahedral cluster and one atom of the interstitial B(12) dumbbell explains the observed charge separation in this high-pressure high-temperature polymorph of boron.
authors.affiliation: Laboratory of Crystallography, University of Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Swastik
authors.initials: S
authors.lastname: Mondal
authors.forename: Sander
authors.initials: S
authors.lastname: van Smaalen
authors.forename: Andreas
authors.initials: A
authors.lastname: Schönleber
authors.forename: Yaroslav
authors.initials: Y
authors.lastname: Filinchuk
authors.forename: Dmitry
authors.initials: D
authors.lastname: Chernyshov
authors.forename: Sergey I
authors.initials: SI
authors.lastname: Simak
authors.forename: Arkady S
authors.initials: AS
authors.lastname: Mikhaylushkin
authors.forename: Igor A
authors.initials: IA
authors.lastname: Abrikosov
authors.forename: Evgeniya
authors.initials: E
authors.lastname: Zarechnaya
authors.forename: Leonid
authors.initials: L
authors.lastname: Dubrovinsky
authors.forename: Natalia
authors.initials: N
authors.lastname: Dubrovinskaia