Abstract
The solid-phase enthalpy of formation (∆H(f, solid)) of energetic materials was generally predicted from the gas-phase enthalpy of formation (∆H(f, gas)) and sublimation enthalpy (∆H(sub)). Here, the standard ∆H(f, solid) of energetic materials is directly obtained from density functional theory (DFT) calculations by computing the enthalpy difference between the solid-phase energetic material and its constituent elements in their reference states. To reduce the errors in DFT calculations, a concept of isocoordinated reaction is introduced, i.e., the reference states are selected based on the coordination numbers of all atoms in the energetic material. This DFT method for ∆H(f, solid) calculation does not require experimental input, data fitting, or machine learning. For more than 150 energetic materials collected from the literature, the mean absolute error (MAE) of ∆H(f, solid) for the DFT method is 39 kJ mol(-1) (or 9.3 kcal mol(-1)) referring to the literature. Our demonstration raises prospects for first-principles prediction of the properties of energetic materials, and the proposed method for ∆H(f, solid) calculation is also promising for other materials.