CRIF:ID- Development of a Pulsed Nozzle, Fourier Transform Rotational Spectrometer Operable Below 1000 MHz for Chemistry Research

CRIF-ID计划的这一奖项将使北得克萨斯大学化学系的Stephen Cooke能够充分表征和改进一种基于腔的、时域的傅里叶变换旋转光谱仪，能够记录1 GHz以下的光谱跃迁。它还将实施低频快速通道版本的实验，以实现光谱特征的快速定位。这种仪器的可获得性在以下方面引起了相当大的兴趣：1.更大和/或更重的化学物种的几何和电子结构特征，而不是用高分辨率的时间域技术常规研究的。2.在20厘米及以上区域同步实验室测量和射电天文测量。低频仪器的可获得性也将有助于实验室检测星际介质中可能存在的大分子。傅立叶变换旋转(微波)光谱仪测量气相分子的旋转能级之间的跃迁。可以分析这些光谱，以洞察所研究物种中原子的排列，本质上是关于其结构的信息。结构信息对于了解化学和生化性质以及反应活性很重要。这个仪器开发项目将由研究生和本科生进行，他们将获得设计和建造尖端最先进仪器的技能。

This award from the CRIF-ID program will allow Stephen Cooke in the Department of Chemistry at the University of North Texas to fully characterize and improve a cavity based, time domain, Fourier transform rotational spectrometer capable of recording spectral transitions below 1 GHz. It will also implement a low frequency fast passage version of the experiment to enable rapid location of spectral features. The availability of such an instrument is of considerable interest in regard to: 1. The geometric and electronic structural characterization of larger and/or heavier chemical species than can be routinely studied with high resolution, time domain techniques. 2. Synchronizing laboratory based measurements and radio-astronomy measurements in the region of 20 cm and above. The availability of a low frequency instrument will also aid in the laboratory detection of large molecules that may exist in the interstellar medium. Fourier transform rotational (microwave) spectrometers measure transitions between rotational energy levels of molecules in the gas phase. These spectra can be analyzed to obtain insight on the arrangment of the atoms in the species under study, in essence information on its structure. Structural information is important for understanding chemical and biochemical properties and reactivity. This instrument development project will be carried out by graduate and undergraduate students who will gain skills in the design and construction of sophisticated state-of-the-art instrumentation.