NH_3和ClO_3对RDX初始热裂解的影响

Effects of NH_3 and ClO_3 on the Initial Pyrolysis of 1,3,5-Trinitro-1,3,5-triazine

用B3LYP/6-31G(d)方法,优化得到RDX及其与高氯酸铵(AP)裂解产物NH3、ClO3形成复合物的稳定构型,计算了RDX及各复合物的N-NO2键解离能。结果表明,复合物中RDX构型变化不是很大,但其CS对称性遭到破坏。RDX与NH3、ClO3结合后其N-NO2键解离能与RDX相比变化不大,NH3、ClO3的存在不影响RDX硝基裂解A位优先于E位的顺序。但一旦复合物裂解,生成的NO2极易与NH3发生反应,放出大量热,从而可引发RDX的后续裂解反应。

The structures of 1,3,5-trinitro-1,3,5-triazine （RDX） and its complexes with the pyrolysis products （NH3,ClO3） of ammonium perchlorate （AP） were optimized by the B3LYP/6-31g（d） method,and the bond dissociation energies of N-NO2 for RDX and its complexes were calculated.The results show that the geometrical configurations of the RDX in the complexes are similar to the RDX structure,but the original CS symmetry of RDX is destroyed.The axial nitryls of RDX in the complexes with NH3,ClO3 are prior to the equatorial nitryls in its pyrolysis process and there are trivial changes on the N-NO2 bond dissociation energies when RDX combines with NH3 and ClO3.However,once the complexes decompose,the product NO2 can react with NH3 more easily.This exothermic reaction may induce the subsequent pyrolysis process of RDX.