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The crystal structure of substituted formamidine salts has been modeled on the basis of a combination of quantum chemistry methods and atom–atom potentials. Based on the new author's method (MICCM) for calculating the enthalpies of formation of salts, which is based on the model of a cocrystal consisting of a mixture of cations and anions and a "quasi-salt" of the neutral components of the salt itself, the formation enthalpy is calculated as the average between the enthalpies of formation of these two structural components for salts various formamidines and the contributions of the corresponding cations to the calculation scheme are given. The results are in good agreement with the experimental data obtained by combustion calorimetry. [ABSTRACT FROM AUTHOR]

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 quantumchemical 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. [ABSTRACT FROM AUTHOR]

Simulation of crystal structures of series 1(2)‐R‐1(2)H‐[1,2,3]triazolo[4,5‐e][1,2,3,4]tetrazine 5,7‐dioxides, 1,5,7‐trioxides, 4,6‐dioxides and 3,4,6‐trioxides was carried out using an original technique based on the method of atom‐atom potentials and quantum chemistry. The effect of the position of the substituent in the triazole ring on the change in the crystal structures of these compounds and their thermochemical characteristics was studied for the first time. For some of synthesized compounds, thermochemical characteristics were investigated and differential scanning calorimetry curves were obtained. Detonation parameters were calculated, on the basis of which the prospects for the use of the considered compounds were assessed. [ABSTRACT FROM AUTHOR]