Strong Be−Be and Zn−Zn Bonded Aromatic Complexes of Ethyne

Abstract

Quantum chemical calculations reveal that ethyne (C2H2) can be a very good fragment to create strong Be−Be and Zn−Zn interactions. The complexes are thermodynamically stable in which Be2 and Zn2 fragments act as electron donors towards C2H2 fragment acquiring Be2δ+ and Zn2δ+ states. The partial positive nature of Be2 and Zn2 fragments made their electronic structure to be described adequately by single reference character. Introduction of electronegative F atom as in C2F2 results in shorter Be−Be and Zn−Zn distances. Bonding analyses reveal that all these complexes feature delocalized π bond resulting in aromaticity.