Electroabsorption and Related Spectroscopic Studies of Bimetallic Tetraiminoethylenedimacrocyclic Complexes: Corroboration of Valence Electron Delocalization.

Mixed-valence complexes (chemical species containing multiple metal centers that exist formally in more than one oxidation state) represent ideal models for testing and understanding optical and thermal electron transfer.1 Though the prototypical mixed-valence ion, the Creutz-Taube ion, was first studied over 25 years ago,2 new mixed-valence complexes continue to be made and studied. Among the more interesting of these new complexes are a series of bimetallic tetraiminoethylenedimacrocycles (M2TIEDL4, where L is CH3CN, dimethylformamide (DMF), or Cl-, and M is Fe or Ru), 1, first reported by Spreer and co-workers.3