Systematicab initioconfiguration-interaction study of alkali-metal clusters. II. Relation between electronic structure and geometry of small sodium clusters

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 Liₙ 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 Na₈ and Na₄ can be expected.