抄録
Ab initio molecular orbital (MO) and density functional theory (DFT) calculations were applied to zinc clusters comprising 2-192 atoms. The minimum bonding length, average binding energy, and electron population of the 4p orbital (N4p) were evaluated as a function of the number of atoms (n) after optimization of the cluster structure. The clusters show a drastic transition in their properties from molecular to clusters at around n=4, and gradually exhibit bulk properties with increasing n. Polarization of the clusters' electric charge was also predicted—negative charging inside the cluster and positive charging at the surface—attributable to nonuniform distribution of electrons belonging to the orbits of respective atoms. The highest occupied molecular orbital - lowest unoccupied molecular orbital (HOMO-LUMO) transition energy gap with changing n, the relation between the N4p value, the cluster stabilization energy, and the influence of defects in the crystalline N4p are also discussed.
