Ab initio current density maps for circulene computed using the ipsocentric CTOCD-DZ/6-31G**//RHF/6-31G** method show that in both planar [3a (D7h)] and non-planar, saddle-shaped [3b (C2)] geometries this molecule sustains similar counter-rotating rim (diatropic) and hub (strongly paratropic) currents. A survey of the orbital contributions to the current density reveals that 3 like corannulene (1) is a 4d + 4p system with just eight magnetically active and 20 magnetically inactive π electrons. The graph-theoretical Hückel-London model describes the ring-current patterns of [n]circulenes in terms of a coupling strength (the ratio of radial and tangential resonance integrals) that charts the variation from the decoupled con-rotating currents of the [n]annulene-within-an-[m]annulene model to the fully coupled counter-rotating currents of the real [n]circulene. © 2002 Elsevier Science B.V. All rights reserved.
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