Organic cyclic difluoramino-nitramines: infrared and Raman spectroscopy of 3,3,7,7-tetrakis(difluoramino)octahydro 1,5-dinitro-1,5-diazocine (HNFX)
Organic cyclic difluoramino-nitramines: infrared and Raman spectroscopy of 3,3,7,7-tetrakis(difluoramino)octahydro 1,5-dinitro-1,5-diazocine (HNFX)
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DOI：
10.1002/jrs.2210
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发表时间：
2009-08
影响因子：
2.5
通讯作者：
P. Weck;Cedric L. Gobin;Eunja Kim;M. Pravica
中科院分区：
文献类型：
--
作者：
P. Weck;Cedric L. Gobin;Eunja Kim;M. Pravica
我们提出了第一个振动结构调查的3，3，7，7-四（二氟氨基）八氢-1，5-二硝基-1，5-二氮杂环辛（HNFX）-更一般地说，一类新的宝石双（二氟氨基）取代的杂环硝胺高能材料的成员-使用相结合的理论和实验方法。优化的分子结构和振动光谱的Ci…使用密度泛函理论方法计算了构成HNFX晶体的对称构象。在室温和常压下，收集了HNFX晶体样品的傅里叶变换红外光谱和拉曼光谱。在B3 LYP/6-311 + + G（d，p）理论水平上，计算的结构参数与X射线衍射数据的平均偏差约为1%，表明晶体场诱导的分子畸变不明显。非常好的协议被发现之间的模拟和测量光谱，允许可靠的分配的HNFX晶体的振动的基本正常模式。由于C-（NF{sub 2}）{sub 2}和N-NO{sub 2}部分在分子均裂断裂过程的初始步骤中至关重要，因此对它们的正常模式进行了详细分析。
We present the first vibrational structure investigation of 3,3,7,7-tetrakis(difluoramino)octahydro-1,5-dinitro- 1,5-diazocine (HNFX) - and, more generally, of a member of the new class of gem-bis(difluoramino)-substituted heterocyclic nitramine energetic materials - using combined theoretical and experimental approaches. Optimized molecular structure and vibrational spectra of the Ci... symmetry conformer constituting the HNFX crystal were computed using density functional theory methods. Fourier transform infrared and Raman spectra of HNFX crystalline samples were also collected at ambient temperature and pressure. The average deviation of calculated structural parameters from X-ray diffraction data is {approx}1% at the B3LYP/6-311 + + G(d,p) level of theory, suggesting the absence of significant molecular distortion induced by the crystal field. Very good agreement was found between simulated and measured spectra, allowing reliable assignment of the fundamental normal modes of vibration of the HNFX crystal. Detailed analysis of the normal modes of the C-(NF{sub 2}){sub 2} and N-NO{sub 2} moieties was performed due to their critical importance in the initial steps of the molecular homolytic fragmentation process.