Observation of Three Intervalence‐Transfer Bands for a Class II–III Mixed‐Valence Complex of Ruthenium

Multiple intervalence-transfer (IT) absorptions (see picture) appear in the near-IR/IR spectra of the mixed-valence complex [Cl3RuII(tppz)RuIIICl3]− (tppz=tetrakis(2-pyridyl)pyrazine), whose X-ray crystal structure and electronic and vibrational spectroscopic features indicate localized-to-delocalized (Class II–III) behavior.