Crystal Structure of Hexaazaoctadecahydrocoronene Dication [HAOC]2+, a Singlet Benzene Dication

See allHide authors and affiliations

Science  27 May 1988:
Vol. 240, Issue 4856, pp. 1185-1188
DOI: 10.1126/science.240.4856.1185


The structures of hexaazaoctadecahydrocoronene, [HAOC]n (n = O, + 2), have been determined by single-crystal x-ray diffraction. Although HAOC is aromatic, its dication has a localized structure that is based upon Jahn-Teller-distorted cyanine/p-phenylenediammonium fragments. The structure is consistent with the singlet ground state as determined by magnetic susceptibility and contrasts with the simplest Hückel expectation of a triplet ground state.