Isolated-pentagon fullerenes

Austin, S. J., Fowler, P. W., Orlandi, G., Manolopou-los, D. E., Zerbetto, F. (1994). Relative stabilities of Cjs isomers - a numerical test of the fullerene isolated-pentagon rule. Chemical Physics Letters, 226(1-2), 219-225. 

Similar calculations were made for the only possible isomer of C70 [11-13] that obeys the isolated pentagon rule [4, 6] and for some of the most stable isomers of the higher fullerenes [11, 14-16]. On the basis of their easily accessible LUMOs and high electron affinities, all stable members of the fullerene family were expected to display very rich cathodic electrochemistry. 

All fullerenes (C ) are composed of sp2 hybridized carbon atoms forming a 3-D network of fused (n - 20)/2 six-membered and 12 five-mem-bered rings. As enshrined in the Isolated Pentagon Rule (IPR), so far, none of the structures isolated have two pentagons fused together. The curvature of the cage results in some strain, and the three angles around a carbon atom sum to 348° instead of the ideal value of 360° for . The [6,6] fusions have most double-bond character and are invariably where complexation occurs. For there are 30 such equiva-... 

There is an infinity of ( 5,6, 3)-spheres that are 5Rq in fact, as die number of vertices goes to infinity, the proportion of such spheres amongst all ( 5,6, 3)-spheres tends to 1. Such fullerenes are said to satisfy the isolated pentagon rule in Chemistry ([FoMa95]>. 

IPR Fullerene fullerene which satisfies the isolated pentagon rule, i.e. there are no edge-sharing pentagonal rings ... 

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