Non-classical (NC), heptagon-containing fullerenes obtained via chlorination-promoted cage transformations: C 76 (NC2a)Cl 24 and C 76 (NC2b)Cl 28 .

High-temperature chlorination of C 76 fullerene with SbCl 5 proceeds via five Stone-Wales rearrangements, resulting in non-classical (NC) C 76 (NC1a)Cl 24 with two heptagons and 14 pentagons partically fused in pairs and triples. C 76 (NC2b)Cl 28 with isomeric carbon cage was obtained by chlorination-promoted cage shrinkage of C 80 via two C 2 losses. The pathways of skeletal cage trasformations, the chlorination patterns, and formation energies are discussed in detail.