Habit prediction of 3,4,5-trinitro-1H-pyrazole in four solvent mediums using a molecular dynamics simulation

Abstract 3,4,5-Trinitro-1H-pyrazole (TNP) is a novel all-carbon nitrated azole energetic compound with excellent potential, whose explosion and safety performance is affected by its crystal morphology. In this study, an attachment energy (AE) model was employed to study the growth habit of TNP in vacuum and predict the results of the growth habit of the TNP crystals grown from benzene, toluene, dichloromethane and water by the molecular dynamics simulation. The interactions between the solvent molecules and crystal faces were analyzed. The period bond chains (PBCs) of the crystal faces were calculated. The TNP crystals were obtained by the natural cooling experiments in benzene, toluene, dichloromethane and water, respectively. The {1 0 0} crystal form had the largest morphological importance for the TNP crystal habit in vacuum, followed by the {0 1 1} and {0 0 1} forms in turn. The crystal morphology was significantly influenced by the he interactions between the solvent molecules and crystal face. There were three different crystal shapes that are flaky, columnar, and blocky. The aspect ratios of the habit in benzene, toluene, dichloromethane and water were 19.42, 5.65, 5.31 and 3.55, respectively. The predicted TNP morphologies qualitatively agreed with those from the experiment.