【作者】 许刚；

【导师】 闵新民；

【作者基本信息】 武汉理工大学 ， 应用化学， 2010， 硕士

【摘要】 含能材料中比较常见的是硝胺类炸药,它们的分子结构中含有硝基官能团,由于它们同时具备高能量、优良的综合性、广泛的来源、日趋成熟的制造工艺等突出特点,它们越来越广泛地被应用到生活的各个领域中。在含能材料分子的理论研究上,稳定性一直是研究含能材料的重要问题,人们提出了多种研究方法,本文采用密度泛函理论(DFT)B3LYP方法,Gaussian03软件包以及Chem3D等软件,选取6-311G的计算基组对五种链状含能分子MNA、MDN、DMNA、EDNA以及OCPX的分子结构进行量化计算,得到五种链状分子的键长、键角、净电荷、键集居数、总能量以及前沿能隙等相关分子的内部信息,同时对比较常见的TATB含能材料进行计算研究,分析分子稳定性和相互作用的影响,对它们性能的研究提出一些理论的解决方法。在五种链状含能分子中,C-N-N的键角由大到小依次是MNA (116.8°)、MDN (116.5°)、DMNA (117.1°)、EDNA (122.1°)、OCPX (122.9°),三种甲胺的键角相近,两种乙胺的键角相差不大,在五种链状含能分子中,分子的稳定性有随着主链的增大而增大的趋势。在五种链状分子中,各原子之间呈现正负电荷相间有规律的排列,在C-N-N-O链上体现的十分明显,这种分子内部净电荷正负相间分布的现象有利于分子的稳定性。MNA、MDN、DMNA、EDNA以及OCPX五个分子当中氮氮键的键积居数最小,它们之间的共价键的键能比碳氮键、氮氮键、氮氧键以及碳氢键小,这说明在MNA、MDN、DMNA、EDNA以及OCPX这五个分子当中对分子的热感性也即热解作用起着决定性的化学键键是N-N键。五类链状分子的能隙都比较低,相比而言,MNA的能隙最大,MDN的能隙最小,稳定性按OCPX、EDNA、DMNA、MDN、MNA的顺序依次递减。计算优化所得到的TATB分子是一个高对称性分子,在TATB分子中,C-N键对TATB分子的结构性能起决定作用,与五种链状类含能分子相比,TATB分子的稳定性更好；TATB分子上面离子的净电荷是正负相间的,这个现象的形成,是氧的诱导极化造成的,净电荷的正负相间有利于TATB分子的稳定性。与五种链状含能分子相比,TATB的能量很大,前沿能隙也比较大,这验证了TATB含能材料的高能量、高稳定性的结论。更多还原

【Abstract】 Nitroamine explosives are a common kind of energetic materials with-NO2. Due to their merit, such as higher energy, excellent comprehensive, wide variety of sourcesand mature manufacturing technology, they are used more and more widely in different areasIn the theory of molecular energetic materials research, the stability has been an important issue in the study of energetic materials, lots of research methods have been proposed.This article studies on the crystal structure of five chain energetic molecular MNA,MDN,DMNA,EDNA and OCPX at 6-311G level with the B3LYP method, and obtain the inner information of molecule, such as their bond length, bond angle, covalent bonds, net charge, Mulliken populations on bonds, total energy and forefront of the energy gap. At the same time, study the common energetic materials TATB,analyzes their influence of stability and reciprocity so as to get some methods to the research on their performance.In five chain energetic molecules, the angle of C-N-N bond’s descending order is MNA(116.8°),MDN(116.5°),DMNA(117.1°),EDNA(122.1°),OCPX(122.9°),the angle of three methylamine is close, the angle of ethylamine is close. The stability has a trend of the increase with the main chain in the five chain energetic molecules. Positive and negative charge arranged in order in five chain molecules. It is obviously reflected in the C-N-N-0 chain, the phenomena of molecule alternating positive and negative is conducive to the stability of the molecular. Mulliken populations of N-N has the least value among the five chain energetic molecules MNA,MDN,DMNA,EDNA and OCPX, Their bond energy are smaller than the C-N bond, N-N bond, N-0 bond and the C-H bonds. We can see that the N-N bond plays a decisive role on the thermal sensitivity of molecular namely pyrolysis among the five chain energetic molecules. The five chain molecules have low energy gap relatively,MNA has the largest energy gap, MDN has the least energy gap, the stability of OCPX, EDNA, DMNA, MDN, MNA decreased in the order.The TATB molecule obtained through optimization calculations is a high molecular symmetry, C-N bond of TATB molecules play a decisive role on the structure and properties, Compared with the five chain energetic molecules, TATB molecules have better stability. The net charge on TATB molecules arranged positive and negative alternately, this is caused by induced polarization of oxygen, the phenomena of molecule alternating positive and negative is conducive to the stability of TATB. Compared with the five chain energetic molecules, TATB has lager energy and the energy gap, it proves the conclusions that TATB energetic materials has higher energy, higher stability.更多还原