Ab initio calculations on the structure of Covington's sesquicarbonate ion

Abstract

Ab initio calculations suggest that the sesquicarbonate ion, H₃C₂O₆^–, may well exist but has a planar structure (6) held together by two hydrogen bonds instead of the ‘sandwich’ structure (1) or (2) proposed by Covington; the planar structures lies 182 kJ mol^–1 below the sum of the energies of bicarbonate ion and (Z,Z)-carbonic acid.