Synthesis,structure and characterization of copper(II) and zinc(II) complexes based on 3-carboxyl-1,2,4-triazole

Two complexes CuL₂(H₂O)₂] (1) and ZnL₂(H₂O)₂] (2) (L?=?3-carboxyl-1,2,4-triazole (L)) have been synthesized and characterized by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the monoclinic space group P ₂(1)/n, a?=?8.632(8)?Å, b?=?9.153(8)?Å, c?=?6.991(7)?Å, β?=?94.279(12)°, Z?=?2, R ₁?=?0.0296, wR ₂?=?0.0918. Compound 2 also crystallizes in the monoclinic space group P ₂(1)/n, a?=?4.937(3)?Å, b?=?18.107(10)?Å, c?=?6.344(4)?Å, β?=?106.839(7)°, Z?=?2, R ₁?=?0.0230, wR ₂?=?0.0556. Extensive intermolecular hydrogen bonds assemble 1 and 2 into three-dimensional (3D) supramolecular architectures, with eight-member H-bonded synthons. Compounds 1 and 2 were also characterized by element analysis, FT–IR, luminescence and EPR studies.