ANTIMONY AND BISMUTH OXIDE CLUSTERS - GROWTH AND DECOMPOSITION OF NEWMAGIC NUMBER CLUSTERS

A series of new ''magic number'' metal oxide clusters are described fo r the group V metals antimony and bismuth. Specific nonstatistical sto ichiometries of MxOy cation and anion clusters are formed preferential ly in the gas phase when oxidized metal is vaporized or when metal is vaporized and combined with gas phase oxygen (e.g., Bi7O10+, Bi9O14+). Essentially the same stoichiometries are seen for antimony and bismut h analogues. The species produced in cluster growth are also produced preferentially by photodissociation of larger clusters. Localized cova lent bonding schemes are suggested for these clusters, and polyhedral cage structures are proposed. The stoichiometries observed require a 3 + metal oxidation state in the small clusters, which shifts over to on e or more 5+ metal atoms in larger clusters.