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The Excited-State Creutz-Taube Ion.

ABSTRACT: The excited-state version of the Creutz-Taube ion was prepared via visible light excitation of [(NH₃ )₅ Ru^II (μ-pz)Ru^II (NH₃ )₅ ]⁴⁺ . The resulting excited state is a mixed valence {Ru^III-δ (μ-pz⋅^- )Ru^II+δ } transient species, which was characterized using femtosecond transient absorption spectroscopy with vis-NIR detection. Very intense photoinduced intervalence charge transfers were observed at 7500 cm^-1 , revealing an excited-state electronic coupling element H_DA =3750 cm^-1 . DFT calculations confirm a strongly delocalized excited state. A notable consequence of strong electron delocalization is the nanosecond excited state lifetime, which was exploited in a proof-of-concept intermolecular electron transfer. The excited-state Creutz-Taube ion is established as a reference, and demonstrates that electron delocalization in the excited state can be leveraged for artificial photosynthesis or other photocatalytic schemes based on electron transfer chemistry.

SUBMITTER: Pieslinger GE

PROVIDER: S-EPMC10092683 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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The Excited-State Creutz-Taube Ion.

Pieslinger German E GE Ramírez-Wierzbicki Ivana I Cadranel Alejandro A

Angewandte Chemie (International ed. in English) 20221018 49

The excited-state version of the Creutz-Taube ion was prepared via visible light excitation of [(NH3 )5 RuII (μ-pz)RuII (NH3 )5 ]4+ . The resulting excited state is a mixed valence {RuIII-δ (μ-pz⋅- )RuII+δ } transient species, which was characterized using femtosecond transient absorption spectroscopy with vis-NIR detection. Very intense photoinduced intervalence charge transfers were ob ...[more]

PMID: 36161441

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