【Abstract】 The pure buckminsterfullerene sample was ablated by pulsed laser beam on a home-made apparatus. From the recorded time-of-flight mass spectra, it is found that,like the positive ions, the larger negative carbon cluster ions could also be formed from aggregation of buckminsterfullerene. The sizes of the cluster ions with highest signal intensities among each polymerized group of ions axe less than exact tfors of 60 and are related to the expermental conditions. The sizes of some cluster boons are odd numbers,so they must have non-fullerene structures.更多还原