Charge Localization in Collision-Induced Multiple Ionization of van der Waals Clusters with Highly Charged Ions

Charge localization in multiple ionization and fragmentation of small argon clusters is reported. The processes are initiated by interaction of the neutral cluster with highly charged ${\mathrm{Xe}}^{q+}\left(5\le q\le 25\right)$. Products are detected by means of multicoincidence time-of-flight methods. A strong dependence of the fragmentation pattern on the Xe charge state $q$ is observed. In particular, we find evidence for formation of multiply charged atomic ${\mathrm{Ar}}^{r+}$ fragment ions up to $r=7\mathrm{}$. Such high charge states have neither been observed in fission of multiply charged van der Waals clusters nor in ion-induced fragmentation of fullerenes or metal clusters. This hints at fundamentally different excitation and fragmentation dynamics.