【摘要】 有机芳香族硝基化合物是重要的含能材料,评价其撞击感度对于认识其安全性能有重要意义。运用密度泛函方法研究了硝基苯和硝基苯胺类炸药芳香性,首次计算了核独立化学位移(Nucleus-Independent Chemi-cal Shifts,NICS),对其芳香性与撞击感度进行了关联。结果表明:对于这两类炸药,芳香性指标NICS值与零点校正能E的乘积和撞击感度之间存在着很好的相关性,相关系数为0.982,明显好于用键级(相关系数为0.78)和能隙(相关系数为0.53)来表征他们的撞击感度。此外,首次使用支持向量机(support vector machine,SVM)建立了36种芳香族炸药化合物分子结构与撞击感度的定量构效关系(Quantitative Structure-property relationship,QSPR)模型:该模型的判定系数(the square of Correlation coefficient,R2)为0.984,交互检验的相关系数(Rc2v)为0.985,因此支持向量机建立的模型能够很好地预测炸药的撞击感度。该文首次获得了表征有机硝基化合物含能材料撞击感度的两条途径,即芳香性指标NICS与零点校正能E的乘积描述符和支持向量机,相关性较现有方法有很大提高。更多还原

【Abstract】 Organic nitro-compounds are very important energetic materials.How to find proper method to evaluate the sensitivity is very difficult.In this paper the aromaticity index-Nucleus-Independent Chemical Shifts(NICS) of nitroaniline and nitrobenzene explosives are calculated by density functional theory(DFT),and the relationship between impact sensitivity and aromaticity is investigated.Results show that there is a good correlation between the products of NICS and the corrected zero point vibration energy E with correlation coefficient 0.982,which is much better than that obtained by the bond order(0.78) and the energy gap(0.53).The nonlinear regression model for 36 nitro-aromatic molecules is developed based on the support vector machine(SVM).Results show that the square of correlation coefficient R2) and cross validation coefficient(R2cv) are 0.984 and 0.985 respectively.Therefore,SVM method is another good tool to predict the impact sensitivity of explosive.更多还原