We present a comprehensive study on the temperature-dependent mid-infrared absorption spectra between 8.4 µm and 11.7 µm for a complete list of C₃-C₄ alkenes, namely propene, 1-butene, cis-/trans-2-butene and isobutene, as well as 1,3-butadiene, from room temperature to roughly 1000 K. The methodology deploys a rapid-tuning, broad-scan external-cavity quantum-cascade laser (EC-QCL) in a shock tube and can provide quantitative absorption information at a rate in excess of 30 cm${}^{-1}$/ms at spectral intervals between 0.35–0.6 cm${}^{-1}$. The experimental procedure was validated with room-temperature, nitrogen-diluted, static spectra measurements for propene, 1-butene, isobutene, and 1,3-butadiene, showing good agreement with existing spectroscopic databases. Spectral measurements were extended to higher temperatures with shock-heated test gas mixtures diluted by argon, at experimental conditions between 600–1000 K and 1.5–2.5 atm. The resulting spectra show strong temperature dependence and represent the first experimental collection of broadband high-temperature absorption spectra for these species. The measured high-temperature spectra are in reasonable agreement with predictions from fixed-wavelength absorption cross section correlations in the literature. The data presented are archived in the Stanford ShockGas-IR database and provide useful expansions of the existing knowledge on molecular absorption in the mid-infrared at elevated temperatures.

我们对C ₃ -C ₄烯烃（丙烯，1-丁烯，顺-/反式-2-丁烯和异丁烯）的完整列表，对8.4 µm至11.7 µm的温度相关的中红外吸收光谱进行了全面的研究。以及1,3-丁二烯，从室温到大约1000K。该方法在激波管中部署了快速调谐的宽扫描外腔量子级联激光器（EC-QCL），可以提供定量吸收信息超过30厘米${}^{-\mathrm{1个}}$/ ms，光谱间隔为0.35–0.6 cm${}^{-\mathrm{1个}}$。通过室温，氮气稀释，丙烯，1-丁烯，异丁烯和1,3-丁二烯的静态光谱测量验证了该实验程序，表明与现有光谱数据库有很好的一致性。在600–1000 K和1.5–2.5 atm的实验条件下，用氩稀释的冲击加热的测试气体混合物将光谱测量范围扩展到更高的温度。所得光谱显示出强烈的温度依赖性，代表了这些物种的宽带高温吸收光谱的第一个实验性集合。所测得的高温光谱与文献中固定波长吸收截面相关性的预测合理地吻合。