Semi-classical description of ionic and electronic dynamics in metal clusters
Résumé
We present a selfconsistent semi‐classical description of metal clusters with explicit ionic background. We show in particular how the flexibility of the Husimi picture allows a proper, self contained, description of ground state as well as dynamical properties of metal clusters. This leads to a coupled electrons + ions molecular dynamics, which may be followed over long times (typically one picosecond). We consider real time dynamics for electrons at a Vlasov‐LDA level and include dynamical correlations by an Ühling‐Uhlenbeck collision term (VUU). We discuss the effect of the Husimi representation on the electronic dynamics and the impact of a constant isotropic differential cross‐section in the UU collision term, as compared to a velocity dependent anisotropic differential cross section. Finally, we show that the VUU approach is capable of curing the artificial dissipation of an initial fermionic distribution function towards a classical Boltzmann equilibrium over long times.