Inner Sphere Electron Transfer - The Creutz-Taube Ion

The Creutz-Taube Ion

In the preceding example, the occurrence of the chloride bridge is inferred from the product analysis, but it was not observed. One complex that serves as a model for the bridged intermediate is the "Creutz Taube complex," 5+. This species is named after Carol Creutz, who prepared the ion during her PhD studies with Henry Taube. The bridging ligand is the heterocycle pyrazine, 1,4-C₄H₄N₂. In the Creutz-Taube Ion, the average oxidation state of Ru is 2.5+. Spectroscopic studies, however, show that the two Ru centers are equivalent, which indicates the ease with which the electron hole communicates between the two metals. The significance of the Creutz-Taube ion is its simplicity, which facilitates theoretical analysis, and its high symmetry, which ensures a high degree of delocalization. Many more complex mixed valence species are known both as molecules and polymeric materials.