Atomistic simulation on pyrolysis mechanism of CL-20/TNT cocrystal explosive

The relationship of reaction kinetic process with temperatures and densities for pyrolysis of CL-20/TNT co-crystal was studied using reactive force field(ReaxFF) molecular dynamics simulation. The evolution distribution of potential energy and total species, decay kinetics and kinetic parameters for thermal decomposition reaction of CL-20 and TNT were analyzed. Product identification analyses show that the breaking of-NO₂ bond from CL-20 molecules is the initial reaction pathway for thermal decomposition of the cocrystal. With increasing the cocrystal density, the reaction energy barrier of CL-20 and TNT molecule decomposition increases correspondingly. The decomposition process of TNT has an inhibition action on the decomposition of CL-20. Final products for thermal decomposition of the cocrystal are N₂, H₂O and CO₂. The production rate decreases in the order of N₂>H₂O>CO₂.