Halogen chalcogenide complexes of osmium(IV)

Abstract

Osmium coordination compounds OsE 2Cl 12, where E is ( 1), Se ( 2) or Te ( 3), and OsS 2O 2Cl 3 ( 4), as well as a simple osmium compound, OsS 4Cl 2 ( 5). were synthesized in halogen-containing non-aqueous solutions. The structures of ( 1, ( 2) and ( 3) were studied by X-ray diffraction, and determination of their magnetic properties, vibrational (IR, Raman) spectra, 35Cl NQR spectra and electronic diffusive reflectance spectra (DRS) was also carried out. The data obtained showed that the formation of a secondary bridge bond OsCl bE between a chlorine atom from the osmium and a chalcogen atom of the ECl t group took place in complexes ( 2) and ( 3). This formation was followed by elongation of the ECl t bonds. The formation of bonds between the central octahedral OsCl 6 polyhedron and the peripheral coordination chalcogen units, by means of chlorine bridge atoms, results in an increase of the chalcogen coordination number to six (3+3), and the formation of the distorted octahedral [ECl 6]. The number of osmium polyhedra bound to the chalcogen polyhedrons depends on their radii. The structure of the S-containing complex is represented as [(SCl 3)] 2 +·[OsCl 6] − where the (Cl 3 + grou acts as a second coordination sphere cation.