Abstract:
Synthesis of polynuclear metal complexes which can exhibit strong intermetallic electronic coupling across the bridge in the mixed valent state is a formidable challenge. Later, the focus has been shifted to the application potential of mixed-valent systems for molecular electronics. In this regard, a wide variety of mixed valent poly-ruthenium complexes have been designed using selective bridging and ancillary functionalities. Ruthenium complexes have been chosen due to their suitability and extended history for valence exchange in coordination chemistry. Our systematic approaches beyond the conventional systems by using sophisticated ligands and by creating more variegated coordination patterns have demonstrated the following fundamental points: (i) Metal-ligand cooperativity chemistry could bring the structural miscellany in the substrate backbone. (ii) Recognition and structural/spectroscopic characterization of rather elusive d4/d5 (RuIV/RuIII) ions derived mixed valent set up. (iii) The emergence of a fascinating coordination chemistry with non-innocent ligands has raised the danger of mistaking radical complexes for mixed-valent intermediates, which could however be differentiated via collective consideration of sophisticated experimental techniques along with theoretical deliberation.