摘要
利用原位粉末X射线衍射法和原位红外光谱法研究了硝基胍(NQ)晶体的热膨胀。结果表明,在30~160℃内硝基胍a-、b-、c-轴的平均膨胀系数分别12.9×10^(-6),^(-1) 0.1×10-6℃^(-1) 和145.5×10^(-6)℃^(-1) ,显示NQ晶体热膨胀呈明显各向异性,且b轴呈负膨胀。NQ的各向异性热膨胀由其各向异性分子间作用引起。随温度升高NQ分子间氢键减弱,分子间距离增大,减少了NQ分子沿b轴的空间位阻,从而在分子间作用力下沿b轴收缩,导致了负膨胀。该结果有助于理解炸药分子堆积对其物理性能的影响。
The thermal expansion of nitroguanidine （NQ） crystal was investigated by means of in situ powder X-ray diffraction method and in situ FT- IR spectra method. Results show that the average thermal expansion coefficients of the a-, b-, c-axis at 30-160 ℃ for NQ are 12.9×10-6℃-1, -10.1 ×10-6℃-1 and 145.5 ×10-6℃-1 , respectively, revealing that the thermal expansion of NQ is obviously anisotropic and thermal expansion along the b -axis is negative. The anisotropic thermal expansion of NQ is caused by the anisotropic intermolecular interaction. The intermolecular hy- drogen bond decreases with the increase of temperature, and the intermolecular distance increases, and the space hindrance of the molecules along the b axis is reduced, which leads to a negative expansion along the b axis.
出处
《含能材料》
EI
CAS
CSCD
北大核心
2015年第12期1231-1234,共4页
Chinese Journal of Energetic Materials
基金
National Natural Science Foundations of China(11372292,11472252 and 11402239)
Science and Technology Found of CAEP(2013A0203006)
关键词
硝基胍(NQ)
负膨胀
晶体结构
氢键
nitroguanidine（ NQ）
negative thermal expansion
crystal structure
hydrogen bond
