A strategy for predicting the crystal structure of energetic N-oxides based on molecular similarity and electrostatic matching

Abstract

Crystal structure predictions are significant and meaningful for the design of high energy materials since different packing modes can greatly influence their properties, such as energy and safety. In view of the difficulty of organic crystal structure predictions, an alternative strategy was proposed in this work based on the packing similarity of “homologous crystals”. As a case study, the crystal structures of two energetic N-oxides were accurately and rapidly predicted by this strategy, that is, using their O-free analogues with known structures to generate initial crystals. Two rules, molecular similarity and electrostatic matching, were put forward to ensure the packing similarity in the practical applications of crystal structure predictions. Despite the limited number of “homologous crystals” of energetic N-oxides, this study is envisioned to provide a new approach to predict crystal structures of other high energy materials.