Royal Society of Chemistry, Physical Chemistry Chemical Physics, 29(16), p. 15367
DOI: 10.1039/c4cp00860j
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A series of planar hetero[8]circulenes and of their doubly charged ions is studied by the NICS and GIMIC methods to interpret the aroromatic properties of these high symmetry species. In accordance with the performed calculations all studied hetero[8]circulenes are found to be nonaromatic compounds because of paratropic and diatropic ring-currents are completely canceled yielding almost zero net current. In a great contrast, the dicationic and dianionic hetero[8]circulenes demonstrate the predominant contribution of diatropic ring currents resulting in the total aromatic character of the studied doubly charged ions. This fact allows us to predict the high stability of dianionic hetero[8]circulenes and to explain extremely high stability of dicationic species observed in the mass-spectra.