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Several phosphatovanadium cluster compounds with embedded halide ions were investigated. They include the chloride (VO)6(O3POSiMe3)8Cl and the fluoride Et4P (sup +) (V2O3)2(O3PPh)4F (sup -) and the methylphosphato and butyl phosphato analogues of the fluoride compound. Both enable the oxidation of 1,4-cyclohexadiene to benzene in hot pyridine mixture. In addition, both have only three oxygen atoms per phosphorus for cluster bonding, thus allowing the phosphorus centers to serve as sites of positive Gaussian curvature.

Recrystallization of the solid [[Cd.sub.10][S.sub.4][([SC.sub.6][H.sub5]).sub.12] from a solution of pyridine and N, N-dimethylformamide (DMF) results in the formation of the cluster [Cd.sub.32][S.sub.14] [([SC.sub.16][H.sub.5]).sub.36][center dot][DMF.sub.4] as pale yellow cubes. The structure consists of an 82-atom CdS core that is a roughly spherical piece of the cubic sphalerite lattice 12 angstroms in diameter. The four corners of the lattice are capped by hexagonal wurtzite-like CdS units, which results in an overall tetrahedral cluster 15 angstroms in diameter. This cluster dissolves intact in tetrahydrofuran where its absorption spectrum reveals a sharp peak at 358 nanometers at room temperature and its emission spectra show a strong broad band at 500 nanometers., The use of very small molecular clusters as synthetic precursors to bulk, extended solids interests both the physics[1] and chemistry [2] communities. In the particular case of semiconductor materials, the [...]