pH-dependent synthesis of a cadmium coordination compound from a compound based on Hpytz ligand [Hpytz = 5-(4-pyridyl)tetrazole]

Reactions of CdSO4·6H2O and Hpytz [Hpytz = 5-(4-pyridyl)tetrazole] under high pH values produced a known compound, [Cd(pytz)2(H2O)4]·2H2O (1), which can be used to prepare [Cd(Hpytz)(SO4)(H2O)2] (2) by adjusting the pH to a lower level using sulfuric acid under hydrothermal conditions. These compounds were characterized by elemental analysis, IR spectroscopy, and single-crystal diffraction. X-ray analysis reveals that 1 features a mononuclear structure, while 2 affords a 1-D polymeric chain structure. Compound 1 displays a 2-D network, while 2 shows a 3-D network by hydrogen bonding interactions. Furthermore, the luminescent properties were investigated at room temperature in the solid state.