Abstract The high resolution vibrational spectrum of ethyl cyanide (C2H5CN) has been investigated in the far-IR using synchrotron-based Fourier transform spectroscopy. The assignment was performed using the Automated Spectral Assignment Procedure (ASAP) allowing accurate rotational energy levels of the four lowest fundamental vibrations of the species, namely the v 13 = 1 @ 205.934099(8) cm−1, and v 21 = 1 @ 212.141101(8) cm−1, v 20 = 1 @ 372.635293(15) cm−1, v 12 = 1 @ 532.699617(16) cm−1 states, to be determined. The analysis not only confirms the applicability of the ASAP in the treatment of (dense) high-resolution infrared spectra but also reveals some of its limitations. Complementary to the infrared study, the pure rotational spectrum of C2H5CN was also studied in selected frequency ranges from 75 to 255 GHz. New observations of a prototypical high-mass star-forming region, G327.3 - 0.6, performed with the Atacama Large Millimeter Array show that vibrational satellites of C2H5CN can be very intense, of order several tens of Kelvin in units of brightness temperature.

中文翻译：

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SOLEIL 和 ALMA 对原型有机腈的看法：C2H5CN

摘要 已使用基于同步加速器的傅立叶变换光谱在远红外区域研究了乙腈 (C2H5CN) 的高分辨率振动光谱。分配是使用自动光谱分配程序 (ASAP) 进行的，允许物种的四个最低基本振动的准确旋转能级，即 v 13 = 1 @ 205.934099(8) cm-1 和 v 21 = 1 @ 212.141101 (8) cm−1, v 20 = 1 @ 372.635293(15) cm−1, v 12 = 1 @ 532.699617(16) cm−1 状态，待定。该分析不仅证实了 ASAP 在处理（密集）高分辨率红外光谱中的适用性，而且还揭示了它的一些局限性。作为红外研究的补充，还在 75 至 255 GHz 的选定频率范围内研究了 C2H5CN 的纯旋转光谱。