O. Schapiro et al., FRAGMENTATION PHASE-TRANSITIONS IN ATOMIC CLUSTERS .3. COULOMB EXPLOSION OF METAL-CLUSTERS, Zeitschrift fur Physik. D, Atoms, molecules and clusters, 41(3), 1997, pp. 219-227
We discuss the role and the treatment of polarization effects in many-
body systems of charged conducting clusters and apply this to the stat
istical fragmentation of Na-clusters. We see a first order microcanoni
cal phase transition in the fragmentation of N alpha(70)(Z+) for Z = 0
to 8. We can distinguish two fragmentation phases, namely evaporation
of large particles from a large residue and a complete decay into sma
ll fragments only. Charging the cluster shifts the transition to lower
excitation energies and forces the transition to disappear for charge
s higher than Z = 8. At very high charges the fragmentation phase tran
sition no longer occurs because the cluster Coulomb-explodes into smal
l fragments even at excitation energy epsilon = 0.