Coexistence of electronic shells and shells of atoms in microclusters

Abstract

Microclusters exhibit electronic shells and shells of atoms, which in some cases coexist in one and the same spectrum and in some other cases shells of atoms exist alone. That is, electronic shells alone never exist. Specifically, if the constituents of a cluster are the neutral atoms themselves (i.e., a delocalization of the valence electrons does not exist), then only shells of atoms appear (proper for either atomic fermions--odd number of electrons--or atomic bosons--even number of electrons). However, if the constituents of a cluster are the ion cores of atoms plus their delocalized valence electrons (i.e., a delocalization of the valence electrons does exist), then a coexistence of electronic shells (due to delocalized valence electrons) and shells of atoms (due to ion cores) appears in one and the same spectrum.