Impact of two-body collisions on explosion dynamics of irradiated clusters

A semiclassical treatment of electrons coupled to classical molecular dynamics of ions is presented. We consider real time dynamics for electrons at a Vlasov-LDA level and include dynamical correlations by an Uhling-Uhlenbeck collision term (VUU), Coupling to ionic motion is explicitly accounted for by means of a pseudopotential. The test case is the Na-41(+) cluster. We study features of high ionization in strong fs laser pulses and the subsequent Coulomb explosion. We find that Vlasov-LDA-MD reproduces the result of a fully quantum mechanical treatment for the electrons. Electron-electron collisions, as included in VUU, have in turn, non-negligible effects on the time scale of Coulomb explosion.