Crystal Structure Prediction of Energetic Materials

The synthesis and experimental testing of energetic materialscanbe hazardous, but their many industrial and military applicationsnecessitate their constant research and development. We evaluate computationalmethods for predicting the crystal structures of energetic molecularorganic crystals from their molecular structure as a first step incomputationally evaluating materials, which could guide experimentalwork. Crystal structure prediction (CSP) is evaluated on a test setof 10 energetic materials with known crystal structures, initiallyusing a rigid-molecule, anisotropic atom-atom force-field approach,followed by reoptimization of predicted crystal structures using dispersion-correctedsolid-state density functional theory (DFT). CSP using the force fieldwas found to provide good results for some molecules, whose knowncrystal structures are reproduced by one of the lowest-energy predictions,but are more variable than typical results for other small organic molecules. Reoptimization of predictedcrystal structures using solid-state DFT leads to reliable predictions,demonstrating CSP as an approach that can be applied in the area ofenergetic materials discovery and development. The performance of crystal structureprediction methodsis assessed on a set of 10 molecular organic energetic materials,demonstrating that these methods are sufficiently reliable to be usedfor the design of new energetic materials.