Molecular dynamics simulation on thermal decomposition mechanism of CL-20 with different polymorphs

The initial thermal decomposition pathways of the supercell structures of ε, β and γ modifications at different temperatures were studied by molecular dynamics simulations, using the ReaxFF force field, the NPT and NVT ensembles and the Berendsen methods. The results show that the initial pathway of different CL-20 polymorphs is only the N-NO₂ dissociation to forming ·NO₂ radical fragments, and the main thermal decomposition products are N₂, H₂O, CO, CO₂, NO₂, NO₃, HNO₂, HNO₃, N₂O₅, N₂O₂ and NO. The reaction rate constants of main products with the same modification increase with the increasing of temperature.