Regular Article

Ionization potentials and charge localization in small charged group 12 clusters^★

Laboratoire de Physique des Solides, CNRS UMR 8502, Univ. Paris-Sud, Université de Paris-Saclay, 91405 Orsay Cedex, France

^a e-mail: tarento@lps.u-psud.fr

Received: 12 March 2019
Received in final form: 4 November 2019
Published online: 17 December 2019

Abstract

For small size, the cluster X_n with X = Hg, Cd or Zn displays a van der Waals bond. A model Hamiltonian has been proposed for the singly (doubly) ionized van der Waals clusters X_n⁺ (X_n⁺⁺). The first and second ionization potentials of X_n have been calculated. A good agreement is obtained with the available experiment values of the first ionization potential of mercury and cadmium. The stability and the metastability of X_n⁺⁺ are discussed. The energy curves versus the bond length for Hg₂⁺⁺, Cd₂⁺⁺ and Zn₂⁺⁺ have been determined. The hole(s) in charged clusters X_n⁺ and X_n⁺⁺ for 2 ≤ n ≤ 7 is (are) mainly delocalized, except for Hg_n⁺ with n ≥ 4 where the hole is localized on two or three sites.