Luminescent Complexes Containing Halogeno-bridged Dicopper(I) Unit {Cu2(µ-X)2} (X = Cl, Br, and I)

Luminescent copper(I) complexes have been extensively studied in recent decades with various ligands showing their rich photophysical and photochemical properties. In this contribution, the luminescent halogeno copper(I) complexes, especially those with a halogeno-bridged dicopper(I) unit {Cu2(µ-X)2}, one of the basic, common structural motifs among the halogeno copper(I) family, are described from the view point of influences of coligands upon their luminescent properties. Discussions are extended to complexes with the halogeno-bridged tetranuclear unit {Cu4(µ3-X)4}, being another common structural motif, to examine the dominant emissive excited states in halogeno copper(I) complexes.