Binary mono-anions with unprecedented anti-aromatic planar tetracoordinate carbon and nitrogen atoms

Abstract

Global minima (CBe₄⁻ and NBe₄⁻) with planar tetracoordinate carbon and nitrogen atoms are stabilized by multicentric bonds. Their unusual anti-aromaticity is due to the strong localized Be–Be bonds preventing the full delocalization of the electrons in the CBe₄/NBe₄ skeleton. These binary mono-anions are expected to be experimentally realized in the gas phase.