Resonance Raman Investigation of Ru(phen)2(dppz)2+and Related Complexes in Water and in the Presence of DNA
Citations Over TimeTop 22% of 1997 papers
Abstract
Resonance Raman (rR) spectroscopy was utilized to gain insight into the electronic structure of dppz (dppz = dipyrido[3,2-a:2‘,3‘-c]phenazine) complexes of Ru(II) and Os(II). The time-resolved resonance Raman (TR3) spectrum of Ru(phen)2(dppz)2+ (phen = 1,10-phenanthroline) collected under 355 nm (fwhm ≈ 10 ns) excitation is consistent with the population of a ligand-centered (LC) 3ππ* state of the dppz ligand. Since emission from the Ru(II) → (dppz) metal-to-ligand charge transfer (MLCT) excited state is observed, both states must possess similar energies. Lowering of the MLCT state energy in Ru(phen)2(F2-dppz)2+ and Os(phen)2(dppz)2+ with respect to that of the 3ππ* state results in the disappearance of the LC 3ππ* excited-state peaks in the rR spectrum, indicative of its fast deactivation to the lower MLCT state in these complexes. Addition of DNA to the samples containing Ru(phen)2(dppz)2+ and Ru(phen)2(F2-dppz)2+ leads to a decrease in intensity of the peaks associated with the intercalating phenazine part of the dppz ligand. Further increase in the DNA:Ru ratio causes broadening of the spectrum. This broadening has been interpreted in terms of strong ππ interaction between the intercalated dppz ligand and the DNA bases.
Related Papers
- → Application of Resonance Raman Spectroscopy to Electronic Structure in Metal Complex Excited States. Excited-State Ordering and Electron Delocalization in Dipyrido[3,2-a:2',3'-c]phenazine (dppz): Complexes of Re(I) and Ru(II)(1995)111 cited
- → Electronic absorption, resonance Raman and excited-state resonance Raman spectroscopy of rhenium(I) and copper(I) complexes, with substituted dipyrido[3,2-a : 2′,3′-c]phenazine ligands, and their electron reduced products(2000)42 cited
- → Triplet state (T1) resonance Raman spectroscopy of phenazine and acridine(1984)15 cited
- [Interaction of DNA with phenazine series compounds].(1999)
- → ChemInform Abstract: Synthesis and Study of a Mixed‐Ligand Ruthenium(II) Complex in Its Ground and Excited States: Bis(2,2′‐bipyridine)(dipyrido(3,2‐a:2′,3′‐c)phenazine‐N4N5)ruthenium(II).(1990)