SIGNATURE OF CRYSTALLINE ORDER IN ULTRA-SMALL METAL-OXIDE CLUSTERS

First principles calculations of the equilibrium geometries, binding e nergies, electronic structure and ionization potentials of SbxOy clust ers reveal that clusters as small as Sb5O7 bear the fingerprint of the ir crystal structure. Electronic structure of even smaller clusters mi mics the bulk behavior. A partial ionic bonding between metal and oxyg en atoms leads to a new family of magic numbers for (x, y) = (2, 3), ( 3, 4), (4, 5) and (5, 7). Simple rules are provided for constructing g eometries of larger magic clusters. (C) 1998 Elsevier Science B.V. All rights reserved.