The Laboratory Study of Interstellar Radicals by Pulsed Beam Fourier Transform Microwave Spectroscopy

在化学系实验物理化学项目的支持下，卫斯理大学的斯图尔特·E·诺维克教授将使用脉冲光束傅里叶变换微波光谱(FTM)来研究自由基。详细的谱线位置和结构将被确定为一些含有乙酰基的碳基自由基，包括C5H3，C4H5的各种自由基异构体，两个异氰基C3N和C5N，以及苯基C6H5。还将研究弱结合非自由基络合物以及在这些放电中产生的纯碳链的弱结合络合物的振动激发态。自由基是一种反应性的瞬时分子物种，具有高度的反应性，难以捉摸，很难产生和研究。自由基在化学反应中是重要的中间体，射电天文学探测到的许多星际分子都是自由基。因此，这项工作对射电天文探测的可能候选者有直接影响。此外，它可能会影响其他领域，其中自由基的存在是重要的，如在理解燃烧机制。

In this project supported by the Experimental Physical Chemistry Program of the Chemistry Division, Prof. Stewart E. Novick of Wesleyan University will study free radicals using pulsed-beam Fourier transform microwave spectroscopy (FTM). Detailed spectral line positions and structures will be determined for a number of carbon-based radicals containing acetylenic groups, including C5H3, various radical isomers of C4H5, two isocyanide radicals C3N and C5N, as well as the phenyl radical, C6H5. Vibrationally excited states of weakly bound non-radical complexes as well as weakly bound complexes of pure carbon chains produced in these discharges will also be examined. A free radical is a reactive transient molecular species that is highly reactive, elusive, and difficult to produce and to study. Radicals are important as intermediates in chemical reactions, and many of the interstellar molecules detected by radio astronomy are radicals. This work therefore has a direct impact on likely candidates for radio astronomical detection. In addition, it may impact other fields where the presence of radicals is important, such as in understanding the mechanisms of combustion.