Three Luminescent Dinuclear Copper(I) Complexes with P^N Ligands: Synthesis, Photophysical Properties, DFT Calculations and AIE Behavior

摘要

Three new BPTA-bridged binuclear copper(I) complexes bearing three different diphosphine ligands, namely, [(CuI)2(Xantphos)2(BPTA)](BF4)2 (Cu1), [(Cu~I)2(Dppp)2(BPTA)](BF4)2 (Cu2), and [(Cu~I)2(Binap)2(BPTA)](BF4)2 (Cu3), have been synthesized and characterized. The X-ray structure analyses of complex Cu3 show that the central copper(I) ion adopts a distorted tetrahedral geometry. Complexes Cu1 and Cu2 exhibit greenish-yellow emission with excited-state lifetime (13μs and 27μs) and photoluminescence quantum yields (6.86% and 0.62%) at room temperature in the solid state. Emission decay measurement and theoretical calculation suggest that the transition nature of their emission could be assigned to ~3MLCT/~3LC excited states. More interesting, complexes Cu1-Cu3 are weakly emissive in solution but become strongly luminescent in solid state, so it has the aggregation induced emission (AIE) behavior.