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Two novel representatives of energetic (1,2,4-triazolyl)furoxans were prepared from the readily available (furoxanyl)amidrazones. Synthesized compounds were thoroughly characterized with IR and multinuclear NMR spectroscopy, elemental analysis and X-ray diffraction data. Analysis of structural features supported by quantum-chemical calculations revealed the main reasons for experimentally observed difference in thermal stability and mechanical sensitivity of both compounds. It was found that 3-cyano-4-(1H-1,2,4-triazol-3-yl)furoxan is more thermally stable (Td: 229 ​°C) than 4-azido-3-(1H-1,2,4-triazol-3-yl)furoxan (Td: 154 ​°C) and the latter compound is also more sensitive to impact and friction. In addition, both heterocyclic assemblies have high detonation parameters (vD: 7.0–8.0 ​km·s−1; p: 22–29 ​GPa) exceeding those of benchmark explosives trinitrotoluene and hexanitrostilbene which enable their usability for various energetic applications.

A new efficient method for calculating the enthalpies of salt formation is proposed. The method is based on a fundamentally new cocrystal model, consisting of a mixture of cations and anions and a “quasi-salt” of neutral components, in fact, of the salt itself, and the enthalpy of formation is calculated as the average value between the enthalpies of formation of these two structural components. Unlike correlation and additive schemes, this method is based on the construction of a real physical model of a salt crystal, for which the molecular geometry of the ions and neutral salt components is preliminarily optimized by quantum chemistry methods. Further, based on the obtained data, the initial models of crystal lattices in the statistically most probable structural classes are constructed with their subsequent optimization by the method of Atom–Atom potentials. For a number of compounds of various chemical classes, the effectiveness of the method for estimating the enthalpy of salts is shown, which surpasses the known methods in terms of calculation accuracy.

Using quantum chemical methods and the original technique based on atom–atom potential methods, the molecular and crystal structure simulation of all possible structural forms of nitrodiaziridines were carried out. The possible pathways of thermal decomposition of nitrodiaziridines were modeled, and the most stable forms were identified. Thermodynamic stability, physicochemical characteristics, and detonation properties were also estimated. The obtained results enable a huge potential of the nitrodiaziridine-based compounds as high-energy materials for a variety of applications.

The thermochemical characteristics of bistetrazole dioxide salts with 7 cations were calculated for various arrangements (1.1; 1.2, and 2.2) of N-oxide groups. The volume-based thermodynamics method, the additive method (Method of Adding of Ions Contributions), and the method for determining the enthalpy of salt formation by mixing the ionic and neutral components of enthalpy (MICCM) were used, the latter of which is in good agreement with the experimental data and gives the best calculated results compared to other methods known in the literature. For an additive approach to estimating the enthalpies of salt formation, the corresponding contributions of anions have been developed, which enables a significant expansion of the range of salts currently available for calculations. The methods of quantum chemistry and atom–atom potentials were used to simulate the crystal lattices of individual compounds and cocrystals in the 11 most frequently implemented space groups for subsequent use of these results in calculations by the MICCM method. Possible previously unknown polymorphic structures of bistetrazole dioxide salts are predicted.