Improved Prediction of Heats of Formation of Energetic Materials Using Quantum Mechanical Calculations

This is the authors' abstract. We don't add key points for this paper.

We present simple atom and group-equivalent methods that will convert quantum mechanical energies of to gas phase heats of formation of CHNO systems. In addition, we predict heats of sublimation vaporization derived from information obtained from the quantum-mechanically calculated electrostatic of each isolated molecule. The heats of sublimation and vaporization are combined with the gas phase heats of formation to produce completely predicted condensed phase heats of. These semiempirical computational methods, calibrated using experimental information, were applied a series of CHNO molecules for which no experimental information was used in the development of the. These methods improve upon an earlier effort of Rice et al. [Rice, B. M.; Pai, S. V.; Hare, J.. Flame 1999, 118, 445] through the use of a larger basis set and the application of group equivalents. root-mean-square deviation (rms) from experiment for the predicted group-equivalent gas phase heats of is 3.2 kcal/mol with a maximum deviation of 6.5 kcal/mol. The rms and maximum deviation of the liquid heats of formation are 3.2 and 7.4 kcal/mol, respectively. Finally, the rms and maximum of predicted solid heats of formation are 5.6 and 12.2 kcal/mol, respectively, an improvement in rms of approximately 40% compared to the earlier Rice et al. predictions using atom equivalents and a basis set (B3LYP/6-31G*).