Theoretical Study of the Mechanism of the Decomposition Process of High Energy Density Materials.

摘要

One of the goals of the HEDM program is the development of high performance monopropellants which are also less toxic than currently used systems such as hydrazine. Included in this effort is the characterization of decomposition mechanisms, as an initial step toward identification of a suitable catalyst. Ab initio quantum mechanical calculations are performed on the decomposition mechanisms of NH2Me2+NO3%, a potential monopropellant replacement for hydrazine. The potential energy surfaces of two gas-phase decomposition processes have been explored: (1) proton transfer and (2) methyl cation transfer reactions. These reaction pathways have been examined for both the isolated cation NH2Me2 + and in the presence of a counter anion, X=Cl, NO3. For X=Cl, transition states for both pathways have been located at the RHF/6-31G* level and the corresponding intrinsic reaction coordinates (IRCs) have been traced. Comparison of activation barriers and reaction enthalpies for these gas-phase decomposition pathways will be presented here.