ON THE COLLISIONALLY INDUCED DESTRUCTION OF SHORT-LIVED AND LONG-LIVED FULLERENE IONS

Collisionally induced destruction of fullerene ions C-n(48 less than o r equal to n less than or equal to 90) has been studied in single-pass and storage ring experiments. The collisionally induced destruction c ross section at 45 keV varies with time for fullerene ions other than those which occupy 'magic numbers' in mass spectra such as C(-)(60)and C-+(70). This observation indicates that these fullerene ions possess high internal energies when they leave the source. It is found that a fraction of these hot ions become stable as a result of cooling on a timescale of milliseconds.