Nitrogen-Rich 5,5'-Bistetrazolates and their Potential Use in Propellant Systems: A Comprehensive Study

A large variety of twice-deprotonated nitrogen-rich 5,5'-bistetrazolates, that is, the ammonium (1), hydrazinium (2), hydroxylammonium (3), guanidinium (4), aminoguanidinium (5), diaminoguanidinium (6), triaminoguanidinium (7), and diaminouronium (8) salts, have been synthesized. Energetic compounds 18 were fully characterized by single-crystal X-ray diffraction (except 8), NMR spectroscopy, IR and Raman spectroscopy, and differential scanning calorimetry (DSC) measurements. With respect to their potential use in propellant applications, the sensitivity towards impact, friction, and electrical discharge were determined. Several propulsion and detonation parameters (e.g., heat of explosion, detonation velocity) were computed by using the EXPLO5 computer code based on calculated (CBS-4M) heats of formation and X-ray densities. Additionally, the performance of 18 in various formulations was investigated by calculating the specific energy and specific impulse of the compounds under isochoric conditions.