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A new 1D polymeric strontium compound [Sr(tza)2(H2O)2]n was synthesized by reaction of tetrazole-1-acetic acid (Htza) with strontium carbonate, and characterized by X-ray single crystal diffraction, elemental analysis and IR spectroscopy. The central Sr(II) atom is coordinated by eight O atoms from 4 tza- ions and two water molecules. A zigzag chain along the c-axis is constructed by the tridentate tza- anion bridging two Sr(II) atoms. Differential scanning calorimetry (DSC) and thermogravimetric-differential thermogravimetric (TG-DTG) analyses were applied to assess the thermal decomposition behavior. The kinetic parameters were obtained by non-isothermal reaction kinetics, and the Arrhenius equation can be expressed as lnk = 22.17-258.2 × 103/RT. The critical temperature of thermal explosion values, ΔS≠, ΔH≠ and ΔG≠ were obtained at 562 K as, -65.71 J mol-1 K-1, 255.51 kJ mol-1 and 291.78 kJ mol-1, respectively. [ABSTRACT FROM AUTHOR]

The title compound 1, [Mn(H2O)6](AMTZ)2(PA)2, contains 4-animo-3,5-dimethyl-1,2,4-triazole (AMTZ) and picrate (PA) and was characterized by elemental analysis, FT-IR spectroscopy and Single-Crystal X-ray diffraction. The space group of compound 1 is triclinic P-1(2), with a = 6.797(2) Å, b = 9.800(3) Å, c = 13.197(4) Å, α=,β=,γ=. The central Mn2+ is octahedral and surrounded by two kinds of centrosymmetric molecules, AMTZ and PA. The compound has an extended 3-D supramolecular structure due to water molecules coordinated though hydrogen bonds to the nitrogen and oxygen atoms and the offset face-to-face π ··· π packing. The differential scanning calorimetry (DSC) analysis shows that two exothermic processes take place at 341.4°C and 473.9°C. The kinetic parameter of the first exothermic process was studied using Kissinger's method and Ozawa's method. This provided the enthalpy of formation (-3337.7 kJ·mol-1), critical temperature of thermal explosion (588.79 K). The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) were, respectively, -209.78 J·K-1·mol-1, 155.50 kJ·mol-1 and 267.75 kJ·mol-1. A flame sensitivity test showed that the 50% firing height (h50) was 20 cm. [ABSTRACT FROM AUTHOR]