Electron capture and energy loss in ∼100 keV collisions of atomic and molecular ions on C60

We have determined absolute attenuation and electron capture cross sections in similar to 100 keV collisions between atomic ions of moderate charge states (He+, He2+, Ar2+, Ar3+, Ar4+, Xe2+, Xe3+, Xe4+) and C-60 molecules in the gas phase. The measured cross-sections support previous findings of the charge dynamics within C-60 from electron capture experiments with higher ionic charges. For a non-negligible fraction of the capture events we observed substantial ionic energy loss (less than or equal to 2 keV), which is ascribed to collisions where the ion passes through the C-60 molecule. Furthermore, we found that a molecular ion (100 keV CO22+) that captures an electron from C-60 can lose similar amounts of energy without dissociating. It is concluded that the predominant contribution to the ionic energy loss comes from electron excitation and ionization. (Int J Mass Spectrom 177 (1998) 51-62). (C) 1998 Elsevier Science B.V.