College of Safety Science and Engineering, Nanjing Tech University, Nanjing, 210009, China.
J Mol Model. 2023 Feb 4;29(3):62. doi: 10.1007/s00894-023-05452-4.
[2,2'-Bi(1,3,4-oxadiazole)]-5,5'-dinitramide (ICM-101), 2,4,6-triamino-5-nitropyrimidine-1,3-dioxide (ICM-102), and 6-nitro-7-azido-pyrazol[3,4-d][1,2,3]triazine-2-oxide (ICM-103) are excellent China-made explosives, but their performance under external electric fields (EEF) has never been explored, especially sensitivity. To study the induction effect of EEF on it, the chemical reactivity, electron localization function (ELF), spectrum, and other parameters were calculated by density functional theory. The results show that the increasing EEF can weaken the △E (△E = E-E) materials, making the stability worse and the sensitivity higher. The proportion of the positive electrostatic surface potential area is also smaller under the increasing EEF, indicating that ICM molecules are becoming more and more unstable. The ELF and localized orbital locator (LOL) decrease with the increase of EEF strength, which suggests that the trigger bond length increases, the E decreases, and the molecular sensitivity increases. When the intensity of EEF increases, the absorption peak of the molecular spectrum gradually redshifts, and even a weak new absorption peak appears, indicating that the color of the material may change. Finally, EEF strength affects electron density, nitro charge, and chemical reactivity parameters.
Gaussian 16 software was used for calculation. The calculation levels are B3LYP/6-311G+ (d, p) and B3LYP/Def2-TZVPP. The optimized structure has a local true minimum energy on the potential energy surface and no imaginary frequency. Multiwfn 3.8 and VMD 1.9.3 were used in this work to analyze the ICM series of energetic material wave functions. The strength range of EEF is 0.000-0.016 a.u., and the increasing gradient is 0.002 a.u.
[2,2'-双(1,3,4-恶二唑)]-5,5'-二硝酰胺(ICM-101)、2,4,6-三氨基-5-硝氨基嘧啶-1,3-二氧化物(ICM-102)和 6-硝-7-叠氮吡唑[3,4-d][1,2,3]三嗪-2-氧化物(ICM-103)是中国制造的优秀炸药，但它们在外部电场(EEF)下的性能从未被探索过，尤其是敏感性。为了研究 EEF 对其的诱导作用，采用密度泛函理论计算了其化学活性、电子定域函数(ELF)、光谱和其他参数。结果表明，增加 EEF 可以削弱△E(△E=E-E)材料，使稳定性变差，敏感性增加。在增加的 EEF 下，正静电表面势能区域的比例也较小，表明 ICM 分子变得越来越不稳定。ELF 和局域轨道定位器(LOL)随 EEF 强度的增加而减小，这表明触发键长增加，E 减小，分子敏感性增加。随着 EEF 强度的增加，分子光谱的吸收峰逐渐红移，甚至出现较弱的新吸收峰，表明材料的颜色可能发生变化。最后，EEF 强度影响电子密度、硝基电荷和化学反应性参数。
使用 Gaussian 16 软件进行计算。计算水平为 B3LYP/6-311G+(d，p)和 B3LYP/Def2-TZVPP。优化结构在势能表面上具有局部真实的最小能量且没有虚频。本文工作中使用了 Multiwfn 3.8 和 VMD 1.9.3 来分析 ICM 系列高能材料波函数。EEF 的强度范围为 0.000-0.016 a.u.，递增梯度为 0.002 a.u.。
