Magnetic criteria of aromaticity in a benzene cation and anion: how does the Jahn-Teller effect influence the aromaticity?

The aromatic/antiaromatic behavior of the Jahn-Teller UT) active benzene cation and anion has been investigated using Density Functional Theory (DFT) calculations of Nuclear Independent Chemical Shifts (NICS) and magnetic susceptibility. NICS parameters have been scanned along the Intrinsic Distortion Path (IDP) for the benzene cation showing antiaromaticity which decreases with increasing deviation from D-6h to D-2h symmetry. Changes in NICS values along the IDP from D-6h to C-2v in the benzene anion revealed non-aromatic character