The interplay of the electronic and atomic structure on the stability of cationic Li5+pO2+ clusters

Cationic Li5+pO2+ clusters (0 less than or equal to p less than or equal to 5) are studied by the use of ab initio molecular dynamics within the local spin density approximation and compared to neutral Li4+pO2 species. The to pologies of the most stable Li7O2 and Li10O2 isomers are shown to change up on ionization. An enhanced stability is obtained in the neutral or ionized clusters whenever the number of the lithiums not bounded to oxygen atoms is equal to half the number p of excess electrons. This results in odd-even o scillations both in the Li detachment energies for the cationic species and the adiabatic ionization potentials of the neutral clusters.