Systematic<i>ab initio</i>configuration-interaction study of alkali-metal clusters. II. Relation between electronic structure and geometry of small sodium clusters

Abstract

The quantum-chemical investigation of the electronic and geometrical structure of neutral sodium clusters carried out with the all-electron Hartree-Fock (HF) or effective-core-potential HF followed by multireference double-excitation configuration-interaction (MRD-CI) procedure demonstrates the complete analogy to the electronic properties of ${\mathrm{Li}}_{\mathrm{n}}$ clusters. The general rules determining the electronic properties of small alkali-metal clusters are again clearly confirmed. Under experimental conditions which do not allow strong cluster fragmentation the large abundances of ${\mathrm{Na}}_{8}$ and ${\mathrm{Na}}_{4}$ can be expected.