Mechanistic investigation on the gas-phase thermal decomposition of triazene-bridged nitro-1,2,4-triazole

Electronic structure methods based on quantum mechanics were employed to characterize elementary steps for the gas-phase thermal decomposition of triazene-bridged nitro-1,2,4-triazole (TBBT). Homolytic C–NO₂ bond scission and ·NO₂ elimination were the most energetically favorable unimolecular paths for the initial decomposition. From there, sequences of unimolecular reactions for daughters of the initiation steps through low-energy β-scission reactions and ring-opening reaction were postulated and characterized. Hydron shift, C–N bond breakage, nitrogen and NO₂ elimination, and small molecules like CN–N=NH obtained were all characterized. Creating a comprehensive network that can be used to develop a detailed limited rate chemical dynamic mechanism for simulating decomposition of TBBT, the results provide the foundation for TBBT’s combustion modeling, and response to its aging, and storage.