First Isomers of Pristine C 104 Fullerene Structurally Confirmed as Chlorides, C 104 (258)Cl 16 and C 104 (812)Cl 24

Isolation and characterization of very large fullerenes is hampered by a drastic decrease of their content in fullerene soot with increasing fullerene size and a simultaneous increase of the number of possible IPR (Isolated Pentagon Rule) isomers. In the present work, fractions containing mixtures of C 102 and C 104 were isolated in very small quantities (several dozens of micrograms) by multi‐step recycling HPLC from an arc‐discharge fullerene soot. Two such fractions were used for chlorination with a VCl 4 /SbCl 5 mixture in glass ampoules at 350–360 °C. The resulting chlorides were investigated by single‐crystal X‐ray diffraction using synchrotron radiation . By this means, two IPR isomers of C 104 , numbers 258 and 812 (of 823 topologically possible isomers), have been confirmed for the first time as chlorides, C 1 ‐C 104 (258)Cl 16 and D 2 ‐C 104 (812)Cl 24 , respectively, while an admixture of C 2 ‐C 104 (811)Cl 24 was assumed to be present in the latter chloride. DFT calculations showed that pristine C 104 (812) belongs to rather stable C 104 cages, whereas C 104 (258) is much less stable.