Login / Signup

The Excited-State Creutz-Taube Ion.

German E PieslingerIvana Ramírez-WierzbickiAlejandro Cadranel
Published in: Angewandte Chemie (International ed. in English) (2022)
The excited-state version of the Creutz-Taube ion was prepared via visible light excitation of [(NH 3 ) 5 Ru II (μ-pz)Ru II (NH 3 ) 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.
Keyphrases