On the temperature dependence of the ionization potential of self-compressed solid- and liquid-metallic clusters

The density functional theory and sum-rule approach are used to calculate the electronic chemical potential of large self-compressed metallic clusters in the stabilized-jellium model and the two-component model that mimic the solid and the liquid state. The ionization potential is defined as the sum of the electronic chemical potential for a neutral cluster, and the ordinary electrostatic contribution . Using the analytic expressions derived, the temperature dependencies of the work function and of the term connected with spontaneous deformation have been estimated. The calculations show noticeable size-shrinkage contributions to the ionization potential. In the two-component statistical version of the density functional formalism, substantial changes induced by a transition from cold clusters to the liquid state are observed.