The Structure and Decomposition Chemistry of Isomer Defects in a Crystalline DADNE

We simulated substitutional stereoisomer defects in a crystalline 1,1-diamino-2,2-dinitroethylene (DADNE) and studied their atomic and electronic structure and decomposition chemistry. We found that molecular gas phase trans- and cis-isomers are 4.6-6.9kcal/mol (0.2-0.3eV) and 11.5-16.1kcal/mol (0.5-0.7eV) less stable than DADNE, respectively, which agrees well with earlier studies. We also established that the substitutional trans-isomer defect in the ideal DADNE crystal significantly affects the thermal stability and chemical and physical properties of the solid DADNE matrix, which may imply the existence of alternative synthesis routes for new materials and gives new insight into initiation of detonation in energetic materials.