Ruthenium Creutz-Taube complex

In this example, the formation of the chloride bridge was not observed experimentally but was inferred from the analysis of the product analysis. The Creutz—Taube complex, shown in Figure 6, is a model for the bridged intermediate. This ion was named after Carol Creutz, who prepared it while working with Taube. Pyrazine is the bridging Hgand here. In the Creutz—Taube ion, the average oxidation state of Ru is +2.5. Spectroscopic studies have shown that the two Ruthenium centres are equivalent, which indicates the ease with which the electron hole communicates between the two metals. Many more complex mixed valence species are known both as molecules and polymeric materials. 

Creutz C and Taube H 1973 Binuclear complexes of ruthenium amines J. Am. Chem. Soc. 95 1086... 

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