Evaluation of solid-state formation enthalpies for energetic materials and related compounds

Solid-state formation enthalpies of energetic materials and related compounds are estimated from the difference between the calculated gas-phase formation enthalpies and sublimation enthalpies. The rms deviation from the observed values is 0.21 kJ/g using the most accurate method. The errors mostly depend on the limitations of the methods available to calculate the gas-phase contribution. For instance, the rms deviation increases by approximately 0.15 kJ/g on going from Density Functional Theory (DFT) to semi-empirical methods for this purpose.