A mixture of higher fullerenes C-76-C-96 was pentafluoroethylated with C2F5I at 250 degrees C affording a mixture of C2F5 derivatives. After separation with high-performance liquid chromatography, the second C2F5 derivative of C-84(16), C-84(C2F5)(12), was investigated by X-ray crystallography and compared with the known isomer in terms of addition patterns and formation energies. Chlorination of a C-84 isomeric mixture with VCl4 at 350-400 degrees C resulted in the formation of C84Cl22. X-ray diffraction study revealed the superposition of several C84Cl22 molecules with different isomeric C-84 cages but the same chlorination pattern.