CS3RE5OSS11, A COMPOUND CONTAINING MIXED RHENIUM OSMIUM CLUSTERS

The sulphide Cs3Re5OsS11 was prepared via a reaction of cesium carbona te with rhenium- and osmium powder in a sulphur-charged hydrogen strea m at 850 degrees C. The X-ray single crystal structure determination r evealed an atomic arrangement in which [Re5OsS8] units are linked by s ulphur-bridges to a three-dimensional framework (space group: Im (3) o ver bar, Z = 8, a = 16.222(2) Angstrom). The (Re5Os)-octahedra are alm ost regular with respect to a 24 valence electron configuration In agr eement with this configuration a weak, nearly temperature independent paramagnetism was measured. The bond lengths between the bridging sulp hur ligands and the (Re5Os)-clusters are shortened, compared to (Re-6) -Clusters, because of the higher charge of the (Re5Os)-octahedra.