Ring Currents in a Proposed System Containing Planar Hexacoordinate Carbon, CB62−

Current-density maps at the coupled Hartree-Fock level calculated in the CTOCD (continuous transformation of origin of current density) approach demonstrate the magnetic response of the hypothetical planar hexacoordinate carbon species, CB(2-)(6). In contrast with the empty CB(2-)(6) framework, which supports paramagnetic currents, the carbon-containing species has a typical diamagnetic pi-ring current that circulates undisturbed by the central atom. In spite of the unconventional nature of the species, the properties of 6pi CB(2-)(6) and 4pi CB(2-)(6) can be rationalised with the same orbital model that accounts for the diamagnetic pi current of benzene and the paramagnetic pi current of planar cyclooctatetraene.