Osmium, supramolecular complexes

Pyrazine, bridged supramolecular complexes, 46 206-213, 240-243 p-Pyrazine complexes, osmium, 37 307 Pyrazolates, ligand with rhodium complex, 44 278 Pyrazoles... 

The electrochemical and photophysical properties of a variety of mixed-metal supramolecular complexes incorporating Ru(II)/Os(II)-polyazine LAs to reactive Rh(III) systems have been investigated. The coupling of Rh(III) to ruthenium and osmium chromophores has been explored in some detail due to the known energy and electron transfer quenching of MLCT states of ruthenium and osmium by Rh(III) complexes in bimolecular processes. The systems studied to date most frequently included tris(bidentate) or bis(tridentate) coordination on Rh(III). While these studies provide considerable insight into the intramolecular excited state dynamics, these coordination environments typically prevent reactivity at the rhodium site. 

Heavy metals, especially the third row transition elements, are useful reagents in biology and biochemistry. The high electron density of these elements (notably tungsten, osmium, platiniim and gold) makes them well suited for revealing aspects of supramolecular structures in electron microscopic images (l). More recently, simple platinum complexes have become widely used in cancer chemotherapy ( ). 

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