Magnetically Induced Current-Density Susceptibility of Circum[]coronenes.

We have calculated the magnetically induced current density (MICD) susceptibility at the all-electron density functional theory level for a series of coronoid molecules of increasing size and compared the MICD susceptibilities with those calculated using the pseudo-π (PP) model. The molecules sustain global diatropic magnetically induced ring currents (MIRCs), whereas paratropic MICD vortices mainly appear inside the benzene rings. The computationally cheaper PP calculations were also employed on circum[]coronene molecules showing that the MICD pattern continues to alternate for odd and even when increasing the size of the molecule. For even , there is a local paratropic MIRC in the middle of the molecule, whereas when is odd, the PP models do not sustain any paratropic MIRC pathways. The global diatropic MIRC flowing mainly along the outer edge of the molecule increases with increasing suggesting that there is no size limit of the MIRC of circum[]coronene molecules. There are seven weakly aromatic Clar rings in the middle of the PP model of the circum[]coronene molecules with odd , whereas circum[]coronene molecules with even have no Clar rings. There are no Clar rings in the outer part of the circum[]coronene molecules with > 1.