含硝基炸药分子的结构与感度研究

【作者】 董洁；

【导师】 朱俊；

【作者基本信息】 四川大学 ， 原子与分子物理， 2005， 硕士

【摘要】 键离解能（bond dissociation energy,BDE）是影响化学活性的一个基本因素,也是自由基过程中的关键因素。高能炸药的分子裂解一直被认为是炸药爆炸的一个重要环节,特别是炸药的起爆和引发被认为与炸药分子中最弱键离解能量有很大关系。而含硝基类炸药是很重要的一类高能炸药,分子中C-NO₂键是该类炸药爆炸和热分解的引发键。本文基于对分子结构的分析,计算了断裂C-NO₂键和N-NO₂键的离解能,并以此为判据深入研究了其与炸药感度的关系。 本文采用密度泛函理论中的B3LYP方法,取6-31G^*基组,分别对含alphaC-H键的硝基芳香族炸药以及几种硝胺类炸药的分子结构和能量进行研究,讨论了含alpha C-H键的硝基芳香族炸药分子中C-NO₂键离解能的强弱与其位置的关系,并且通过计算两种系列分子的键离解能,将其与该分子对应的感度相比较和关联,发现此两类分子的键离解能与感度之间确实存在一定的关系;另外,我们还特别对一种能够合成复杂含能材料的重要初始原料——二硝基尿素（DNU）的结构和性质进行DFT的研究;最后,由于分子间的相互作用一直是量子化学研究的一个热点领域,其在化学、物理、生物乃至高能体系分子的爆炸性质方面的理论探讨都具有重要意义。本文对最简单的三原子水分子的二聚体的相互作用进行研究。利用从头算方法,在HF/6-31G^**水平下得到了水二聚体势能面上的7种优化构型,通过对分子中原子间最短距离、分子间质心距离与各构型相互作用能的关系进行分析、比较,得到了最稳定的构型。希望通过对这种最简单的水分子二聚体的研究,对以后的炸药分子间的相互作用的研究有所帮助。更多还原

【Abstract】 The bond dissociation energy(BDE) is a basic factor which can influence the chemical activity and is an import factor in the course of the free group. It is always considered that the molecular decomposition of energetic materials is an essential step of the explosion of the energetic materials, especially explosion and solicitation of the explosives have great relation with BDE. The nitroaromatics is a very important energetic materials. And the C-NO2 bond is the solicitation bond of explosion of this kind of explosives. Based on the analysis of the molecular structure, this paper calculated the BDE for removal of the NO2 group, and investigated deeply the relation between the BDE and sensitivity.In this paper, the molecular structure and energy of two kind of nitroaromatics were calculated by B3LYP method of Density Functional Theory ( DFT) and the 6-31g* basis set. And the relationship between the C-NO2 bond BDE and the position of C-NO2 in nitroaromatic molecules with alpha C-H linkage was examined . At the same time, this paper calculated the BDE of the two kind of explosive molecules, and discussed the relationship between the BDE and sensitivity. Additionally, we studied the structure and property of a useful raw material — dinitrourea which can compose complex energetic materials using DFT. At last, because of the importance of the intermolecular interaction, this paper investigated the interaction of H2O dimmers. By comparing the relation between the distances of the two H2O molecular mass center and the interaction energy with that between the shortest interatomtic distances of the dimer and the interaction energies, the most stable structure is achieved. The work of the study of H2O dimmers’ interaction may conduce the research of the interaction in the explosive molecules.更多还原