Synthesis, crystal structure, thermal decomposition and sensitivity properties of (AIM)(HTNR) and (AIM)(PA)

Two new energetic compounds (AIM)(HTNR) and (AIM)(PA)(AIM=2-azidoimidazole, TNR=2,4,6-trini- troresorcinol, PA=picric acid) have been prepared by AIM(2-azidoimidazolium) and TNR(2,4,6-trinitroresorcinol) or PA(picric acid) and characterized by elemental analysis and FTIR spectrum. Their crystal structures were determined by X-ray single-crystal diffraction analysis. The obtained results show that (AIM)(HTNR) crystal belongs to monoclinic, P2 ₁/c space group, a=1.1306(2) nm, b=0.70305(14) nm, c=1.7398(4) nm, β=106.91°, V=1.3231(5) nm ³, D _c=1.778g/cm ³, Z=4, R ₁=0.0524, wR ₂[I >2σ(I)]=0.1067 and S=1.092 and (AIM)(PA) crystal belongs to monoclinic P21/c space group, a=0.80303(16) nm, b=0.81395(16) nm, c=2.0471(4) nm, β=93.93(3)°, V=1.3349(5) nm ³, D _c=1.683 3g/cm, Z=4, R ₁=0.0784, wR ₂[I >2σ(I)]=0.1814 and S=1.098. Both the compounds have electrostatic attraction and hydrogen bonds, which contribute to making the constructions more stable. The decomposition of the two compounds was studied via differential scanning calorimetry(DSC) and thermogravimetry-derivative thermogravimetry(TG-DTG) techniques at a heating rate of 10°C/min, and the results show that both the compounds underwent one intensive exothermic decomposition stage. Sensitivity tests reveal that the title compounds were insensitive to friction and im- pact and sensitive to flame and could be applied in potential pyrotechnics.