EQUILIBRIUM-CONFIGURATIONS OF FLUOROMETHYL-C-60 RADICALS - AN EPR ANDTHEORETICAL-STUDY OF INTERACTIONS WITH THE C-60 SURFACE

The EPR spectra of CH2FC60 and CHF2C60 are presented, and the dominant conformer for each species identified. It is suggested that the equil ibrium configurations of fluoromethyl-C60 radicals are determined not by steric effects, but by Coulombic interactions between highly polari zable fluorine atoms and the C60 surface. The dominant effect appears to be a preference for the conformation in which a fluorine atom lies over the pentagon adjacent to the point of attachment of the CH(n)F3-n reater-than-or-equal-tongreater-than-or-equal-to0) ligand. These effe cts are discussed on the basis of semi-empirical calculations of the e quilibrium structures and charge distributions on the C60 surface.