Construction of New Insensitive Explosives: Fused N₅-Chain N¹,N³,N⁵-(1,2,3,4-Tetrazole -5-Nitro)-1,3,5-Triamino-2,4,6-Trinitrobenzene Derivatives

A series of N¹,N³,N⁵-(1,2,3,4-tetrazole-5-nitro)-1,3,5-triamino-2,4,6-trinitrobenzene derivatives containing fused N₅-chain were investigated theoretically. Density functional theory has been employed to calculate their geometric, electronic structures, band gaps, and heats of formation at the B3LYP/6-31G** level. The detonation performance was evaluated by using Kamlet-Jacobs equations based on the calculated densities and HOFs. The thermal stability of these compounds was investigated by bond dissociation energies, energy gaps and molecular electrostatic potentials. Results show that there are good linear relationships between detonation velocity, detonation pressure and the number of nitro groups. Most of the designed derivatives have higher detonation velocity (D), detonation pressure (P), and specific impulse (I_sp) than those of RDX. D and I_sp of molecule L even outperform those of CL-20. Some of the title molecules have higher h₅₀ (impact sensitivity) than RDX (except for D, H, L). According to the quantitative standard of energy and stability as insensitive high energetic materials (IHEMs), molecules I and J essentially satisfy this requirement. These results provide basic information for molecules design of novel IHEMs.