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For the structurally rigid homometallic dinuclear complexes (ttp)Ru(tpy-tpy)Ru(ttp)⁴⁺ and (ttp)Ru(tpy-ph-tpy)Ru(ttp)⁴⁺, we have obtained ground-state absorption spectra and transient-absorption difference spectra at room temperature and luminescence spectra and lifetimes in the temperature interval from room temperature to the rigid matrix (90 K); the solvent was acetonitrile or butyronitrile (tpy is 2,2‘:6‘,2‘‘-terpyridine, ttp is 4‘-p-tolyl-2,2‘:6‘,2‘‘-tpy, and ph is 1,4-phenylene). The gathered spectroscopic data indicate that after absorption of visible light, formation of the luminescent metal-to-ligand charge transfer (MLCT) excited states takes place, which involves the bridging ligand (BL). Since we found that (ttp)Ru(tpy-tpy)Ru(ttp)⁴⁺ is a good luminophore (λ_max = 720 nm, Φ = 4.7 × 10^-3, and τ = 570 ns) while both (ttp)Ru(tpy-ph-tpy)Ru(ttp)⁴⁺ (λ_max = 656 nm, Φ = 1.1 × 10^-4, and τ = 4 ns) and the reference mononuclear …