Multistage transformation and charge effect during the fragmentation phase transition in atomic clusters

Compared with the macrosystem case, the phase transition occurring in fragmenting cluster systems depicts a much richer story. However, most experimental observations have been restricted to an extremely partial view of this picture due to the technical limitations of a large-range scan of the energy deposited in a selected cluster system. Here, taking charge-selected C-60(3+) and C-60(4+) as model systems, we experimentally explore the fragmentation phase transition (FPT) over a large energy range and directly observe some of the most important features of the FPT, the multistage transformation, and the charge effect.