Completion of a fourier transform microwave spectrometer to study molecular ions and radicals

分子离子和自由基在常温常压下是高活性的中间产物。尽管它们的寿命很短，但这些实体非常重要，因为它们驱动了许多化学过程，如燃料的燃烧、生产塑料的聚合、天体的形成和伤口愈合中的氧化应激。尽管分子离子和自由基是许多化学反应的基础，但人们对它们的结构和运动知之甚少，因为很难在实验室中以适合于详细实验研究的时间尺度产生和捕获它们。本申请涉及购买必要的设备，以完成傅里叶变换微波光谱仪的建设。在形成稳定产物之前，反应物质将在低温和低压下在超音速射流中稳定下来。该仪器将用于测量曼尼托巴大学各种分子离子和自由基的旋转光谱。将对光谱进行分析，以获得有关分子结构和运动的极其精确的信息。这些细节对于预测分子离子和自由基在其他环境中的化学反应性是必要的。目前，微波光谱仪由于缺乏真空泵来抽离微波腔而无法运行。高真空对这项研究至关重要，因为这项技术依赖于超音速射流来冷却和隔离瞬态分子。其次，必须实施计算机控制系统来操作光谱仪。这需要购买软件和五张计算机卡。最后，现有的微波合成器以前用于测量中性、闭壳类物质的光谱，不适合探测离子和自由基。因此，资金被要求购买一个更强大的，通用的微波信号发生器，以满足所提议的研究计划的具体需求。

Molecular ions and radicals are highly reactive intermediates at normal temperatures and pressures. Despite their short lifetimes, these entities are of great importance as they drive numerous chemical processes such as combustion of fuels, polymerization to produce plastics, formation of astronomical objects and oxidative stress in wound healing.Although molecular ions and radicals are fundamental to many chemical reactions, little is known about their structures and motions because it is difficult to produce and trap them in the laboratory on time scales suitable for detailed experimental study. This application concerns the purchase of the necessary equipment to complete the construction of a Fourier transform microwave spectrometer. Reactive species will be stabilized in a supersonic jet at low temperatures and pressures before stable products are formed. This instrument will be used to measure rotational spectra of a variety of molecular ions and radicals at the University of Manitoba. The spectra will be analyzed to obtain extremely accurate information about molecular structures and motions. These details are necessary to predict the chemical reactivity of molecular ions and radicals in other environments.At present, the microwave spectrometer is not operational as it lacks vacuum pumps to evacuate the microwave cavity. High vacuum is essential for this research as the technique relies on a supersonic jet to cool and isolate the transient molecules. Secondly, a computer control system must be implemented to operate the spectrometer. This requires the purchase of software and five computer cards. Finally, the existing microwave synthesizer was used previously for measuring spectra of neutral, closed shell species and is not suitable for probing ions and radicals. As a result, funds are requested to purchase a more powerful, versatile microwave signal generator that meets the specific needs of the proposed research program.