Abstract:
Published data on fullerenes $\mathbf C_{72}$ to $\mathbf C_{86}$ which obey the isolated pentagon rule (IPR) are generalized. Analysis of unstable isolated-pentagon-rule fullerenes is carried out and the instability criteria are formulated. Two main reasons for the instability of IPR fullerene molecules are identified: their radical nature and/or local overstrain. The classification of fullerenes and a revised isolated pentagon rule are presented.
The bibliography includes 119 references.