Dissociation of cluster ions

The loss of monomers following electron impact ionization causes a significant enhancement of the intensity anomalies ('magic numbers') in mass spectra of xenon clusters. The dissociation rates are measured on a microsecond timescale for clusters containing between 10 and 79 atoms. Each anomaly in the dissociation rates corresponds to an intensity anomaly ('magic number') in the mass spectrum. We have also carried out measurements on the dissociation of multiply charged cluster ions. Triply charged CO2 clusters of size n approx=114 break extremely asymmetrically, the doubly charged carrying 92% of the mass. (Author)