摘要
为研究钝感炸药3,4-二硝基吡唑(DNP)与高能炸药六硝基六氮杂异伍兹烷(CL-20)分子间相互作用,基于密度泛函理论(DFT)优化了DNP/CL-20复合物的结构,得到六种稳定构型;运用自然键轨道(NBO)、电子密度拓扑和约化密度梯度(RDG)分析了复合物中分子间相互作用类型。从CL-20引发键的键长、键解离能、键级和相关硝基电荷与复合物电子密度差等方面分析了分子间相互作用对CL-20感度的影响。结果表明,DNP/CL-20复合物中存在分子间氢键和范德华作用,包括N—H…O、C—H…O和N…O、O…O作用。硝基电荷和电子密度差分析表明这些分子间作用影响了CL-20分子的电荷分布和电子密度分布,改变CL-20引发键稳定性,导致其感度下降。CL-20引发键键长、键级、键解离能和键临界点电子密度的变化量之间具有良好的线性关系。六种构型的相互作用能大小排序为:构型Ⅳ<构型Ⅵ<构型Ⅲ<构型Ⅴ<构型Ⅱ<构型Ⅰ。
To investigate the intermolecular interactions between insensitive explosive 3,4-dinitropyrazole( DNP) and high-energy explosive hexaazaisowurtzitane( CL-20),the structure of DNP/CL-20 complex was optimized based on a density functional theory( DFT),six kinds of stable configurations were obtained. The types of intermolecular interaction in complexes were analyzed by natural bond orbital( NBO),electron density topology and reduced density gradient( RDG). The effects of intermolecular interactions on the sensitivity of CL-20 were analyzed from the bond length,bond dissociation energy,bond order of CL-20 trigger bond and the relative charges of nitro group and electron density difference of complex. Results show that the intermolecular hydrogen bond and van der Walls force,including the interactions of N—H…O,C—H…O and N…O,O…O exist in DNP/CL-20 complexes. The analysis of nitro charges and electron density difference show that these intermolecular effects affect the charge distribution and electron density distribution of CL-20 molecules and change the stability of CL-20 trigger bond,resulting in a decrease of its sensitivity. There are good liner relationships among the variations of the bond length,bond dissociation energy,bond order of CL-20 trigger bond and electron density at the bond critical point. The interaction energy of six configurations in the text increases in the order of structure Ⅰ<structure Ⅲ<structure Ⅳ<structure Ⅱ<structure Ⅵ<structure Ⅴ.
出处
《含能材料》
EI
CAS
CSCD
北大核心
2018年第3期201-209,共9页
Chinese Journal of Energetic Materials
基金
应用物理化学国家重点实验室基金资助
