Two coordination polymers with 3-hydrazino-4-amino-1,2,4-triazole as ligand: Synthesis, crystal structures, and non-isothermal kinetic analysis

Two coordination polymers, [Mn₂(HATr)₄(NO ₃)₄·2H₂O]_n (1) and [Cd ₂(HATr)₄(NO₃)₄·H ₂O]_n (2), were obtained from the corresponding metal nitrate with 3-hydrazino-4-amino-1,2,4-triazole (HATr) and characterized through elemental analysis and IR spectroscopy. The structures were determined by single-crystal X-ray diffraction. The results show that both complexes crystallize in the triclinic P-1 space group and have six-coordinate distorted octahedral structures, which are made up of infinite 1-D chains running along the a axis of metals linked by bridging-chelating HATr ligands. The coordination sites are in agreement with the computational results. Additionally, the decomposition temperatures were determined by differential scanning calorimetry and the kinetic parameters were calculated using Kissingers and Ozawa-Doyles methods; the energies of combustion for 1 and 2 were -7186.25 and -6922.53 kJ M^-1 and the enthalpies of formation were obtained as -1002.35 and -457.27 kJ M^-1, respectively.