关键词: 苯, 叠氮基, 硝基, 密度泛函, 爆轰性能, 热分解机理

The geometries of the nitro and azido substituted derivatives of benzene were optimized at the B3LYP/6-31G* level of density functional theory, the detonation velocity and pressure were calculated with the Kamlet-Jacobs method and eleven candidates satisfying the energetic requirements for high energy density compound (HEDC) were found. The bond dissociation energies (BDE) of the possible trigger bonds were computed for these candidates and the activation energy (E_a) of the pyrolysis process following “furoxan mechanism” were also evaluated for the candidates with the adjacent nitro and azido groups. The calculated results show that E_a is much lower than BDE, implying that when there are adjacent azido and nitro groups in molecule, the stability of compounds will be greatly decreased and the pyrolysis happens in “furoxan mechanism”. Otherwise, the pyrolysis will be initiated from the rupture of C-NO₂ or C-N₃ bond. The calculated BDE are essentially larger than 200 kJ/mol and all E_a are larger than 100 kJ/mol, therefore, the eleven candidates basically satisfy the energetic and stability requirements as HEDC.

Key words: benzene, azido, nitro, density functional theory, detonation property, pyrolysis mechanism