ALKALI CLUSTERS - BEYOND THE JELLIUM SPHERE

Ionic pseudohamiltonians, which replace core electrons in atomic calcu lations, are used to build a new jellium-like model which describes el ectronic ground state and excitation properties of atomic clusters. As an application, we successfully describe the plasmon resonance in Lit hium, Sodium, and Potassium clusters with Little additional effort and considerable improvement over the conventional jellium model.