Redox-active ruthenium(II) σ-arylacetylide wires for molecular electronics incorporating insulating chains

The preparation and properties of novel carbon-rich mono-, bi-, and tri-metallic ruthenium complexes terminated with protected thiol functions for further surface binding are reported. These new structurally rigid complexes include a short chain (SC) or a long (LC) saturated chain between the terminal linking functions and the conjugated carbon-rich pathway in order to increase contact resistance. They display low oxidation potential, and IR studies of the neutral complexes and of their various oxidized forms indicate the high bridging ligand implication in the oxidation processes and charge delocalization. These molecules are expected to facilitate coulomb blockade behaviour in molecular junctions, and are thus excellent candidates to contribute to the establishment of the structure-property relationships of metal containing molecular wires.