Characterization and properties of a new energetic co-crystal composed of trinitrotoluene and 2,6-diaminotoluene

Abstract A 1:1 co-crystal of TNT and 2,6-diaminotoluene were prepared by solvent evaporation method. The structure of the co-crystal was determined via single crystal and powder X-ray diffraction techniques. The diffraction data analysis revealed that the co-crystal is mainly formed by hydrogen bonding (amino-nitro) and donor-acceptor Π-Π stacking. Besides, Hirshfeld surfaces and associated fingerprint plots of the co-crystal were examined and the results showed that the structures are stabilized by H⋯H, O⋯H, O⋯O and C⋯C (Π-Π) intermolecular interactions. The TNT: 2,6-diaminotoluene co-crystal shows significantly reduced impact sensitivity relative to pure TNT. The difference between the impact sensitivity of co-crystal and the impact sensitivity of TNT is due to having different intermolecular interactions observed in the co-crystal structure. This comprehensive study about the formation of co-crystal has resulted in alteration of vital properties including density, oxygen balance, melting point, decomposition temperature, crystal packing and detonation performance (sensitivity, velocity, pressure). The obtained results highlight that co-crystallization provides the newly discovered energetic material with attractive properties, and is an effective way to modify existing energetic material. As a consequence, the advanced and safer energetic material can be created without chemical synthesis.