The unimolecular thermal decomposition mechanism of syn, anti-N,N '-Dinitrourea (DNU)

摘要: Study on the thermal instability of N,N'-Dinitrourea (DNU) is very important for its use as an energetic precursor. Thermal decomposition mechanism DNU studied by in situ pyrolytic Fourier transform infrared spectroscopy with temperature program and density functional theory calculations at B3LYP level. The experimental results have shown that nitryl group molecule initially broken, followed rearrangement or reaction simultaneously. All reactions are nearly complete prior to 100 degrees C resulting formation N2O, NO2, CON, CONH NO2NH2. Theoretical confirmed syn, anti conformation play a key role process N-N bonds were broken firstly increase temperature. plotted potential energy curve via corresponding bond length showed cleavage condensed-phase was highly reversible typical radical recombination zero barriers initial step. Finally, possible pathways N2-N5 homolysis following proposed. final products NO2NH2, detected experiments, formed alpha-cleavage hydrogen atom radicals (C) 2011 Combustion Institute. Published Elsevier Inc. rights reserved.