Study On The Mechanism Of Molecular Reaction Of Energetic Materials

Energetic Materials have a wide range of applications in military, industrial, civil, aviations and so forth. Therefore, the micro performance and synthetic reaction mechanism of energetic materials are the research focus all the time. Especially, the defects existing in the energetic materials have significant effects on the character of materials, and synthesizing energetic materials with high energy density is one of the most important investigations currently.In the present work, cyclotrimethylene trinitramine(RDX) and furoxan, two kinds of representative energetic materials, are investigated theoretically. The investigation mainly divides into two parts. In part one, the optimization and micro performance of monocrystal, supercell and defective crystal are calculated based on MS program package with GGA/PBE basis set. Based on the optimization of RDX, the geometrical configurations of RDX crystal are obtained. We mainly focus on comparing the energy band gaps, density of states, the values of HOMO minus LUMO, defect formation energy and so on between RDX crystal and defective crystal. Based on comparing our calculated results with the experimental values, we find that the results obtained using GGA/PBE basis set are close to the experiment. For the RDX defective crystal, the energy bond gaps of defective crystal decrease obtained from the figures of energy bond gap and state density. In addition, the obvious changes of the electron cloud distribution are found from the values of HOMO minus LUMO between defective crystal and well-defined crystal. And the defect formation energies are very low based on our calculations. The existence of crystal defect makes the RDX crystal more active and easier to detonate. In the second part, we mainly focus on the synthetic reaction mechanism of 3,4-nitro furazan. Two primary types of synthetic reactions are introduced, one is using glyoxime and nitric acid to synthesize 3,4-nitro furazan; the other is using two nitromethane potassium salt to synthesize 3,4-nitro furazan based on the interaction between nitrogen pentoxide and nitric acid. In the case of gas phase and liquid phase, the reactants, transition states and products are optimized. Though calculating reaction potential energy barriers, structures of transition states, imaginary frequency and so forth, the reaction path can be obtained. Finally, the furoxan with high energy density can be synthesized.