THE STONE-WALES MAP FOR C-60

The possible Stone-Wales (pyracylene) rearrangements amongst C-60 fullerenes generate a graph in which buckminsterfullerene is linked to 1709 of the other 1811 fullerene isomers. Only one major bottleneck exists on this main map; all routes to icosahedral C-60 pass through a single isomer of C-2v symmetry. When energies of all isomers computed in the semi-empirical QCFF/PI model are combined with the map, it is found that stability generally decreases with the number of Stone-Wales steps away from the icosahedral isomer and that the 877 most stable isomers are on the main map. Implications of the map for the pentagon and fullerene road models of C-60 formation are discussed.