Synthesis, crystal structures and magnetic properties of Pyrazole-Carboxylic acid complexes

Three new complexes, {[Ni2(3-PCA)2(DMAP)4(H2O)2]·2H2O}2, [Cu2(3-PCA)2(4-PP)2·2H2O]n, and [Cu2(4-PCA)2(2,2′-bpy)2·2H2O]n, are synthesized by the solvothermal method with pyrazole-3-carboxylic acid or pyrazole-4-carboxylic acid as the main ligands and 2,2′-bipyridine, 4-dimethylaminopyridine, or 4-phenylpyridine as auxiliary ligands. The crystal structures of the three complexes are determined by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis, and Fourier transform infrared analysis. The magnetic detection proves that the three complexes are all antiferromagnetic.