Pyrolysis of CL20-BTF Co-crystal via ReaxFF-lg Reactive Force Field Molecular Dynamics Simulations

To obtain detailed information on the potential energy, the evolution of species, the initial reaction paths, and thermal decomposition products, we conducted simulations on pyrolysis process of CL20/BTF co-crystal using the ReaxFF/lg reaction force field, with temperature set at 2000 K to 3000 K. With the analysis of evolution curves of potential energy based on exponential function, we obtain the overall characteristic time. Via a description of the total package reaction with classical Arrhenius law, we obtain the activation energy of CL20/BTF co-crystal: E_a=60.8 kcal/mol. Based on the initial path of CL20/BTF co-crystal thermal decomposition we studied, we conclude that N-NO₂ bond of CL20 molecules breaks first, working as a dominant role in the initial stage of thermal decomposition under the condition of different temperatures, and that all CL20 molecules completely decompose before BTF molecular regardless of different temperatures. We also find that the main products of CL20/BTF co-crystal are NO₂, NO, NO₃, HNO, O₂, N₂, H₂O, CO₂, N₂O, and HONO, etc., on which the temperature forms certain influence.