Nitrogen-rich salts based on 5-hydrazino-1H-tetrazole: A new family of high-density energetic materials

High-density energetic salts that contain nitrogen-rich anions and the 5-hydrazino-1H-tetrazolium cation were synthesized. All salts were fully characterized by vibrational spectroscopy (IR), multinuclear (¹H, ¹³C) NMR spectroscopy, elemental analysis, differential scanning calorimetry (DSC), and impact sensitivity. Four compounds were characterized by single X-ray diffraction. The results show that the extensive hydrogen bonding interactions between the cations and anions form a complex 3D network, which contributes greatly to the high density of the 5-hydrazinotetrazolium salts. It was also found that the incorporation of hydrazino groups into a heterocyclic ring increases the heat of formation and overall nitrogen content of the entire molecule. Some of these salts exhibit reasonable physical properties, such as good thermal stability (T_d = 173.7-198.6°C), reasonable impact sensitivities (IS = 4-40 J), and excellent specific impulses (I_sp = 196.1-288.7 s). In addition, detonation properties of the energetic salts obtained with EXPLO 5.05 identify them as competitively energetic compounds, and in some cases are superior to those of HMX.