Resonance Raman and time-resolved resonance Raman studies of ruthenium(II) complexes of 2,2′-bipyridine and 5-monomethyl-2,2′-bipyridine. Evidence for polarization of the 3MLCT state electron density in the asymmetric ligand

✍ Scribed by Shelly M. Treflert-Ziemelis; James R. Kincaid

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 557 KB
• Volume: 25
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/jrs.1250251107

✦ Synopsis

Abstract

The resonance Raman and time‐resolved resonance Raman (TR^3^) spectra of ruthenium(II) complexes containing the asymmetric (RR)(5‐methyl‐2,2′‐bipyridine) ligand, Ru(5‐mmb), and its methyl‐deuterated analogue, Ru(5‐d~3~‐mmb), are reported. The spectra are compared to those of tris(2, 2′‐bipyridine)ruthenium(II), Ru(bpy), and tris(5,5′‐dimethyl‐2,2′‐bipyridine)ruthenium(II), Ru(5,5′‐dmb), and its deuterated analogue, Ru(5,5′‐d~6~‐dmb). The ground‐state spectrum for the asymmetric chelate is interpretable in terms of vibrationally isolated fragments with the exception of the modes involving the inter‐ring and adjacent bonds. In addition, the TR^1^ spectra are shown to be consistent with slight polarization of the (triplet) metal‐to‐ligand charge‐transfer, ^3^MLCT, excited‐state charge distribution toward the pyridinc fragment of the chelated anion.