Study of Electron Correlations in Pb n2+-Clusters

Abstract

The ground state properties of Pb-clusters are investigated using a many-body Hamiltonian with intra and inter-atomic Coulomb interactions. By solving the model exactly we obtain that Pb is metastable (lifetime τ > 1040s) and that it has isosceles geometry (bondangle Θ ≃ 124°). The importance of electron correlations for the stability of doubly charged clusters is discussed. By comparison between the exact solution and several variational approaches we particularly show that both the metastability and isosceles shape of Pb result mainly from antiferromagnetic quantum spin-fluctuations.