Synthesis, crystal structures and thermal stabilities of zinc coordination polymers containing the 3-hydrazino-4-amino-1,2,4-triazole ligand

Two zinc coordination polymers, {[Zn(HATr)(2)](NO3)(2)}(n) (1) and {[Zn-2(HATr)(4)](ZnCl4)(NO3)(2)center dot H2O}(n) (2), were synthesized from reactions of 3-hydrazino-4-amino-1,2,4-triazole dihydrochloride (HATr2HCl) with Zn(NO3)(2). The polymers were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), elemental analysis, and differential scanning calorimetry. The crystal structures revealed that 1 and 2 have 1-D-chain structures, which were further assembled to form 3-D-frameworks by hydrogen bonds. Thermal analyses showed that these two compounds have thermal stability up to 280 degrees C. The energies of combustion, enthalpies of formation, critical temperatures of thermal explosion, entropies of activation (Delta S-not equal), enthalpies of activation (Delta H-not equal), and free energies of activation (Delta G(not equal)) were also measured and calculated. Furthermore, the sensitivities of 1 and 2 toward impact, friction, and static were determined, which revealed that 1 and 2 were less sensitive than Ni(N2H4)(3)(NO3)(2). [GRAPHICS] .