Investigation on a series of 3-nitro-1,2,4-triazol-5-one based energetic derivatives: Molecular design and screening

Density functional theory calculations at B3LYP/6-311G(d,p) level were employed to investigate the relationships between the structures and properties of 3-nitro-1,2,4-triazol-5-one based high energy density materials (HEDMs). The results show that all the designed compounds possess high positive heats of formation and the -N-3/-N(sic)N- substituents were found to be the effective structural units to improve the heats of formation. The calculated detonation velocities and detonation pressures indicate that substituting the X-NO2/-N(sic)N- groups were very useful for enhancing the detonation properties of these designed compounds. In view of the bond dissociation energies of the weakest bonds, it reveals that most of the derivatives have acceptable thermal stabilities and the -CN groups were beneficial to improve their thermal stabilities. Overall, the effects of the energetic groups on all the parameters combined with those of the different bridges. Compared to those of 1,3,5-trinitro-1,3,5-triazinane and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane, four compounds (A7, B7, D7 and E7) were screened as possible HEDMs and their electronic structures were fully investigated to give better understanding of physicochemical properties and theoretical support for further experimental synthesis.