An EELS study of the effect of 2 keV Ar+ ion irradiation on thin C-60 films

The ion beam (2 keV Ar) induced amorphization of thin fullerene films has been studied by in situ electron energy loss spectroscopy. The diminution of the intensity of characteristic peaks in the EELS spectrum was used to deduce a cross section for the destruction of the C-60 molecules of (0.82 +/- 0.2) X 10(-14) cm(2). The cross section is somewhat smaller than that expected using scaling arguments from the results of more energetic ion bombardment (100-300 keV). The differences are interpreted in terms the secondary processes which occur within the collision cascade surrounding the ion as it slows down in the solid.