Structural investigation of homonuclear Pt₂ and heteronuclear PdPt complexes containing a metal–metal bond bridged by hydrido and sulfido ligands

The complex [Pt₂(μ-H)(μ-S)(dppe)₂](PF₆) undergoes a displacive order–disorder transformation at ca 230 K. The low-temperature structure is ordered with one cation–anion pair as the asymmetric unit in space group P2₁/n. At room temperature the b axis is halved and the space group is P2/n, imposing crystallographic twofold rotation symmetry on both ions; the anion shows major disorder and there is probably minor disorder in the cation, but its internal geometry remains essentially unchanged. The heteronuclear complex [PdPt(μ-H)(μ-S)(dppe)₂](PF₆) is isostructural with the Pt₂ complex at room temperature. All three structures have been determined crystallographically and both complexes have been extensively characterized by NMR spectroscopy, unambiguously confirming the genuine heteronuclear nature of the mixed-metal complex and the presence of the bridging hydride ligand.