Fragmentation of charged antimony clusters induced by collision with a solid surface

The impact energy dependence of the collision of size-selected antimony clusters with the (1000) basal plane of highly oriented pyrolytic graphite has been studied in a new time-of-flight mass spectrometer arrangement. Main fragmentation channels fur positively charged cluster ions Sb-n(+) (5 less than or equal to n less than or equal to 12) are loss of neutral Sb-2 or Sb-4 units and formation of Sb-3(+) and Sb-5(+) fragment ions, which can be explained by the stability of the formed products. In contrast, during impact of Sb-n(-) (3 less than or equal to n less than or equal to 7) no fragment ions are detected, instead an intense electron emission is observed.