Recent advances for assessment of the condensed phase heat of formation of high-energy content organic compounds and ionic liquids (or salts) to introduce a new computer code for design of desirable compounds

Abstract

The condensed phase heat of formation of organic compounds as well as ionic liquids or salts is an important thermodynamic parameter for the evaluation of their energy contents, performances, and sensitivities. For using these materials as components of fuels, propellants or explosives, chemical industries should produce the compounds with high positive heat of formation because they can provide high heat of combustion or detonation performance. In contrast, their thermodynamic stability may decrease with higher positive values in their heats of formation. Experimental values of the condensed phase heats of formation for high energy content-neutral and ionic compounds are scarce in the literature. This work reviews reliable models for prediction of the condensed phase heat of formation of important classes of organic and ionic liquid energetic compounds. A novel easy to handle and user-friendly computer code is introduced for prediction of the condensed phase heat of formation using suitable and reliable predictive methods. The reliability of the new computer code is checked for organic compounds containing energetic groups -O-O-, –N3, –ON=O, –NO2, -ONO2 and –NNO2 as well as high nitrogen content materials and imidazolium- or triazolium-based ionic liquids (or salts). The values of the root mean square (rms) deviations of the condensed phase heat of formation by the new computer code/ quantum mechanical approaches for 11 neutral energetic organic compounds, 14 high-N content compounds, and 72 imidazolium- and triazolium-based energetic ionic liquids or salts are 45.8/78.0, 79.4/105.3, and 39.8/318.7 kJ/mol, respectively. Thus, the reliability of the outputs the new computer code is higher than the computed results from complex quantum mechanical methods, especially for imidazolium- and triazolium-based energetic ionic liquids or salts, wherein they need high-speed computers, specific computer codes and expert users.