Multiply charged neon clusters: failure of the liquid drop model?
We have analyzed the stability and fission dynamics of multiply charged neon cluster ions. The critical sizes for the observation of long-lived ions are n2=284 and n3=656 for charge states 2 and 3, respectively, a factor 3 to 4 below the predictions of a previously successful liquid-drop model. The preferred fragment ions of fission reactions are surprisingly small (2<or=n<or=5); their kinetic energy distributions peak at 200 meV or below. The size of these fragments and their average kinetic energies are much less than predicted by the liquid-drop model.