On the magnetic criteria of aromaticity in topologically spherical molecules: theoretical tools for the magnetic response of giant fullerenes C240 and C540

Abstract

Magnetically induced three-dimensional current densities, net bond current strengths and divergence of the isotropically averaged Lorentz force density have been used to characterize the magnetic response of giant I_h-fullerenes containing 240 and 540 carbon atoms. The weakly diamagnetic response of C₆₀ is also confirmed for these larger fullerenes, which do not fulfil the 2(n + 1)² rule for spherical aromaticity. The presence of peculiar paratropic ring currents local to 6-membered rings is demonstrated. Their appearance is due to the superposition of migrating diatropic ring currents around each paratropic loop.