Nitrobenzenic explosives can have high energy density and low impact sensitivity. In this work, the density functional theory (DFT) charge density of 50 nitrobenzenic molecules was analyzed using the Distributed Multipole Analysis (DMA) method to investigate the impact sensitivity of their explosives. The DMA monopole, dipole and quadrupole electric multipoles localized on the atoms of a molecule provide a very detailed picture of the molecular charge density and have a clear chemical interpretation. The DMA multipoles of each molecule were used to develop models correlating molecular charge properties and impact sensitivity of nitrobenzenic explosives, which is quantified by the quantity h₅₀. Three models previously applied to 17 nitroaromatic molecules (J. Phys. Chem. A 115, 9055, 2011) are now examined for a larger dataset of 50 molecules. Model 1 used the nitro group charge as a single parameter for h₅₀ prediction, Model 2 additionally included the quadrupole values of the benzene ring atoms (a measure of charge delocalization) and Model 3 included the dipole moment (indicator of site polarization) of the nitro groups of each molecule, as well as the average C−NO₂ bond distance, which quantifies bond strength. Two additional new models that include the quadrupole values of the nitro group were also proposed. The original three models (Models 1–3), as well as the new models (4‐5), applied to the set of 50 nitrobenzenic molecules, displayed good results even when compared with the previous work. Among the computed DMA electrical multipole values, two proved to be essential for developing a good model, as found before for the smaller set: the DMA quadrupole values of the ring atoms that quantify the degree of electronic delocalization in the ring and the total DMA charge (monopole) values of the explosophore nitro group.

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炸药分子电荷性质与撞击敏感性之间的相关性：硝基苯衍生物

硝基苯炸药可能具有高能量密度和低撞击敏感性。在这项工作中，使用分布多极分析（DMA）方法分析了50个硝基苯分子的密度泛函理论（DFT）电荷密度，以研究其炸药的撞击敏感性。位于分子原子上的DMA单极，偶极和四极电多极子提供了分子电荷密度的非常详细的图像，并具有清晰的化学解释。每个分子的DMA多极用于建立与硝基苯炸药的分子电荷特性和撞击敏感性相关的模型，该模型由数量h ₅₀量化。先前适用于17种硝基芳族分子的三种模型（J. Phys。Chem。A 115，9055，2011年）现在检查了更大的50个分子的数据集。模型1使用硝基电荷作为h ₅₀预测的单个参数，模型2另外包含了苯环原子的四极值（电荷离域的量度），模型3还包括了苯环原子的偶极矩（位极化的指标）。每个分子的硝基以及平均C-NO ₂粘结距离，量化粘结强度。还提出了另外两个新模型，其中包括硝基的四极值。应用于三个50个硝基苯分子的原始模型（模型1-3）以及新模型（模型4-5）即使与以前的工作相比也显示出良好的结果。在计算出的DMA电多极值中，有两个事实证明对于建立一个好的模型至关重要，这在较小的集合中已经发现：量化环中电子离域度的环原子的DMA四极值和总DMA电荷硝化硝基的（单极）值。