The combustion mechanism of guanidine nitrate (GN) in the gas phase was investigated, and a detailed chemical kinetics model based on quantum chemical calculations was developed. 39 reactions associated with GN combustion were identified and added to our previous model. Optimized structures of reactants, products, and transition states were obtained at the ωB97X-D/6-311++G(d,p) level of theory and the total electron energies of such structures were calculated at the CBS-QB3 level of theory. Transition state theory was used to calculate the kinetics parameters from the quantum chemistry calculations. Detailed chemical reaction calculations revealed the combustion behavior and mechanism of a GN and basic copper (II) nitrate (BCN) mixture. At the initial temperature of 1173 K, the GN/BCN mixture has four zones in the flame structure: the first ignition, the first flame, the second ignition, and the second flame. The combustion reaction is triggered by the HNO3 decomposition to OH· and NO2·, and the radicals attack CN3H5(the first ignition). Remaining CH5N3 is consumed by self-decomposition: CH5N3 → NH3 + HNCNH (the first flame) and then HNCNH, NH3 and NOx gas burn out (in the second ignition and flame).
guanidine nitrate, gas-generation agent, combustion, kinetic model, ab initio calculation