Simulation of RDX Decomposition Interacting with Shock Wave via Molecular Dynamics

Cylotrimethylenetrinitramine (RDX), with the chemical formula C۳H۶N۶O۶,is an energetic organic molecule used widely in military and industrial commodities ofexplosives. By stimulating RDX through exerting temperature or mechanical conditionssuch as impact or friction, decomposition reaction occurs at a very high rate. Moleculardynamics techniques and LAMMPS code with Reactive Force Field (ReaxFF) potentialwere employed to simulate initiation of RDX. Potential energy variations of the systemwere calculated over time for five different temperatures up to ۱۰۰ ps. The products ofdecomposed system with respect to time were calculated at each stage of stimulation fordifferent values of temperature and thermal initiation stimulation energy in NVT andNVE ensembles. The activation energy of decomposition was calculated ۲۰.۲۳۰kcal.mol-۱ through Arrhenius equation. The minimum required temperature to produceH۲ with temperature decomposition was about ۲۵۰۰ K and production times for severalconditions were calculated. The amount of nitrogen and hydrogen production wereincreased with raising temperature and reached the maximum value at ۳۰۰۰ K. Theminimum impetus energy required to form the light species H۲ is ۶۶ kcal.mol-۱.`