Molecular Dynamics Simulation on Thermal Decomposition Mechanism of 4-Amino-3,5-Dinitro Pyrazole

摘要

4-amino-3,5-dinitro pyrazole is a new type of high energy explosives. By means of molecular dynamics, quantum chemistry, chemical reaction kinetics, "the smallest bond order" and "mid-point electrostatic potential" thermal decomposition mechanism of LLM-116 in gas phase was studied. Results show that the initial thermal decomposition step for LLM-116 was C-NO2 bond dissociation. H-transfer reaction wasn’t the main initial step, although the energy barrier of H-transfer reaction was lower, because its reverse reaction was much easier to occur. In addition, catalytic effect of NO2 was investigated. Results show that energy barrier for decomposition of LLM-116 with the existence of NO2 is much lower than that without existence of NO2, i.e. NO2 could accelerate the decomposition of LLM-116.