A thiocyanate-bridging dimeric cyclometalated iridium(III) complex: Synthesis, structure and phosphorescence behaviours towards metal ions

A new neutral dimeric cyclometalated iridium complex containing bridging thiocyanate ligands, [{Ir(μ-SCN)(pqcm)2}2] (1, pqcmH = 2-phenyl-quinoline-4- carboxylic acid methyl ester), has been synthesized and structurally characterized. The photoluminescence (PL) spectrum of 1 shows emission maximum at 638 nm with a lifetime of 0.11 μs and the PL quantum yield is ca. 0.012. The phosphorescence behaviours of 1 towards different solvents and metal ions were also investigated and the strong phosphorescence quenching by acetonitrile and two equivalents of Hg2+, Cu2+ and Ag+ ions were observed.