AN ANALYSIS OF THE 94 POSSIBLE ISOMERS OF C60F48 CONTAINING A 3-FOLD AXIS

The structures and stabilities of all 94 isomers of C60F48 in which th ere is at least a three-fold axis have been calculated using the AM1 H amiltonian and the program MOPAC 6.0. Two structures, of D-3 and S-6 s ymmetry, are substantially more stable than all the other structures, These two predicted isomers are the only two that have been experiment ally observed. An analysis of all 94 isomers reveals that stability is enhanced if the six carbon-carbon double bonds are localised along si x pent-hex edges of the truncated icosahedral structure of C-60, rathe r than along hex-hex edges, and if the double bonds are separated from each other as much as possible.