FISSION OF MULTIPLY-CHARGED ALKALINE-EARTH METAL-CLUSTERS

We have studied the fission of multiply photoionized alkaline earth me tal clusters having charges up to Z = +5 by means of high-resolution t ime-of-flight mass spectrometry. The determined appearance sizes can b e compared to results of simple model calculations assuming that both fragments can still be treated as metallic liquid droplets. In this ca se the measured appearance sizes for the alkaline earth metals are fou nd to be smaller than the ones predicted by the calculations. However, if one fixes the small fragment to be an atomic ion, good agreement b etween measurement and theory is acheived.