ABINITIO MINIMAL BASIS SET CALCULATIONS ON C-60MU

The simplest known adduct of C60 fullerene is C60Mu which shows an exp erimental muSR spectrum very similar to that of C2H4Mu, the muonium ad duct of ethylene. This suggests that the region affected by the additi on of muonium (the defect) is very localised on the fullerene surface. To test this interpretation ab initio restricted Hartree-Fock calcula tions have been carried out on three different levels of relaxation of the C60Mu geometry. Calculations have also been carried out on cluste rs C18H12Mu and C30H12Mu to investigate the extent to which the proper ties of this defect depend on the whole C60 structure.