A novel luminescent iridium(I)–cadmium(II) binuclear complex displaying a long-lived metal-to-ligand charge-transfer excited state. Synthesis and structural characterisation of I(CO)₂Ir(µ-Ph₂Ppy)₂CdI₂ [Ph₂Ppy = 2-(diphenylphosphino)pyridine]

Abstract

The first binuclear Ir^I–Cd^II complex to be structurally characterised, I(CO)₂Ir(µ-Ph₂Ppy)₂CdI₂ [Ph₂Ppy = 2-(diphenylphosphino)pyridine], has a donor–acceptor metal–metal bond of length 2.784(1) Å; at room temperature, excitation of a solid sample of the complex with UV light led to a red emission at 739 nm with a lifetime of 6.48 µs that presumably originates from a ³MLCT excited state.

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