Magnetic Property, Heat Capacity and Crystal Structure of Mononuclear Compounds Based on Substitute Tetrazole Ligand.

Three mononuclear compounds formulated as {M[(2-1H-tetrazol-5-yl)pyridine] 2 (H 2 O) 2 } (M = Fe II ( 1 ), Co II ( 2 ), Cu II ( 3 )) were reported and synthesized. Their space group is monoclinic, P 2 1 /c, revealed by single-crystal X-ray diffraction. Antiferromagnetic interactions exist in Compounds 1 , 2 and 3 , as evidenced by magnetic and low-temperature heat capacity measurements. In addition, their thermodynamic functions were determined by a relaxation calorimeter, indicating that Compound 1 exhibits a Schottky anomaly in low-temperature heat capacity. This work can provide an important fundamental basis for the research of the thermophysical properties of molecular-based magnetic materials.