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I came across this about fullerenes-

All carbon atoms are equal and the undergo sp2 hybridisation. Each carbon atom forms three sigma bonds with three other carbon atoms. The remaining electron at each carbon is delocalized in molecular orbitals which in turn give aromatic character to the molecule. This ball-shaped molecule has 60 vertices and each one occupied by one carbon atom and it also contains both single and double bonds with C-C distances of 143.5 pm and 138.5 pm respectively.

It speaks of fullerenes being aromatic, which would imply that the bond lengths in fullerene must be equal. I am aware of the fact that resonance won't mean that bond lengths be equal in all cases, for example, I found this about naphthalene-

The molecule is planar, like benzene. Unlike benzene, the carbon–carbon bonds in naphthalene are not of the same length. The bonds C1−C2, C3−C4, C5−C6, and C7−C8 are about 1.37 Å (137 pm) in length, whereas the other carbon–carbon bonds are about 1.42 Å (142 pm) long.

I know that such a case in naphthalene is due to dissimilar conjugation as it behaves as a benzene ring joined to a diene. Speaking of graphite, as far as I know, all bond lengths are equal in a layer due to conjugation that is quite comparable to benzene and even better than naphthalene (resonance energy per atom). But I would like to know exactly what happens in a fullerene molecule.

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    $\begingroup$ What you see is what you have: all bonds are conjugated to a certain extent, but not as perfectly as to be called aromatic. $\endgroup$ May 6 at 8:58
  • $\begingroup$ For this question you can easily find much material by simply searching for "fullerenes bond length"., "fullerenes and aromaticity", "fullerenes vs graphite" and so on. Or simply "fullerenes". The main difference should be already in pure geometry, as there are pentagon rings and, but I can be wrong, segments leading to a regular hexagon cannot lead to a regular pentagon. $\endgroup$
    – Alchimista
    May 6 at 9:23
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    $\begingroup$ You'll find a ton of more or less confident claims that fullerenes are aromatic. Just dismiss them as nonsense. $\endgroup$ May 6 at 9:44
  • $\begingroup$ Well yes, I guess I got it, obviously hexagonal and pentagonal rings would mean dissimilarity and there will have to be different bond lengths. $\endgroup$ May 6 at 16:52