Syntheses, crystal structures and luminescent properties of copper(I)-halide complexes constructed by 4-amino-3,5-dimethyl-1,2,4-triazole

A series of copper(I)-halide complexes with 4-amino-3,5-dimethyl-1,2,4-triazole (admtz) as bridging ligands, namely, [Cu2Cl2(admtz)2] (1), [Cu2Br2(admtz)2] (2), [Cu4Br4(admtz)4] (3) and [Cu2I2(admtz)2]n (4), have been synthesized under hydrothermal conditions. X-ray single-crystal diffraction reveals that 1 and 2 show discrete dimeric structures, in which hydrogen bonds link the dimers into 2D networks. Complex 3 adopts a discrete tetrameric structure, which is further connected into a 3D network by C–H···Br non-classical hydrogen bonds. Complex 4 displays a 1D chain that is be further extended into a 2D framework by N–H···I weak interactions. The photoluminescent and luminescence lifetime measurements reveal that 1, 2 and 4 exhibit extensive green-blue phosphorescences in the solid state at room temperature, whereas 3 shows much weaker fluorescent emissions and shorter luminescence lifetimes.