Theoretical Studies on the Energetic Salts of Substituted 3,3′-Amino-N,N′-azo-1,2,4-triazoles: The Role of Functional Groups

Abstract

Thirty energetic salts formed by substituted 3,3′-amino-N,N′-azo-1,2,4-triazoles (A to F) with functional groups (−H, −NH2, −CH3, −N3, −NO2 or −NF2) and acids (HCl (I), HNO3 (II), HClO4 (III), HN(NO2)2 (IV) and HC(NO2)3 (V)) were studied using the density functional theory (DFT). The proton (H1) of an acid plays a more important role in intramolecular interactions than the other H atoms. The electron withdrawing groups −N3, −NF2, and −NO2 improve the positive charge on the H1 compared to that of series A without substituent, which results in the stronger intramoleuclar hydrogen bonding interaction and second perturbation interaction, the opposite effects were caused by the electron donating groups −CH3 and −NH2. −N3, −NF2 and −NO2 gradually enhance density, heat of formation, and detonation performance, while −NH2 and −CH3 lower those characteristics. IIID to IIIF, IVE to IVF, and VE to VF have detonation properties (D = 9.49 km/s to 10.72 km/s, P = 43.51 GPa to 58.14 GPa, Is = 260 s to 291 s); they can b...