199464-01-2Relevant academic research and scientific papers
Heterochelates of ruthenium(II): Electrochemistry, absorption spectra, and luminescence properties
Baitalik, Sujoy,Adhikary, Bibhutosh
, p. 4073 - 4080 (2008/10/09)
A series of heterochelates [Ru(bpy)2(L-X)](ClO4) (1-6) derived from the schiff bases of o-aminophenol and p-substituted (X) benzaldehydes, HL-X (X = NO2, Cl, F, Me, OMe and NMe2) have been synthesized and characterized. Cyclic voltammograms of all the complexes, except 6 (X = NMe2), exhibit a reversible RuII/RuIII and an irreversible RuIII/RuIV oxidation processes. In the case of 6, both the oxidation processes take place reversibly. A linear correlation is obtained by plotting the E1/2 value of RuII/RuIII couple against the Hammett σ+ parameters. The absorption spectra of the complexes are similar showing absorption bands due to dπ-π* (bpy), Schiff base n-π* and π-π* intraligand transitions. A linear correlation is also obtained between vmax (MLCT) and ΔE1/2 (separation between the first oxidation and first reduction couples). The effect of solvents on the MLCT and n-π* absorption bands have been studied. Fluorescent spectral studies have shown that all the complexes luminesce at room temperature and the observed emission bands are due to metal-perturbed ligand-centred transitions.
