Spectroscopic studies of molecular ions and radicals in thenlow frequency regime

分子离子和自由基在常温常压下是高度活性的中间体。尽管它们的寿命很短，但这些实体非常重要，因为它们驱动许多化学过程，如燃料燃烧，聚合生产塑料，形成天体和伤口愈合中的氧化应激。虽然分子离子和自由基是许多化学反应的基础，对它们的结构和动力学知之甚少，因为很难在适合详细实验研究的时间尺度上在实验室中产生和捕获它们。该研究计划将高分辨率光谱技术与离子源和质谱法相结合，以获得一系列分子离子和自由基的旋转和振动光谱。实验将在马尼托巴大学和加拿大光源进行，并涉及超音速喷射膨胀以冷却和分离不稳定分子。这有助于延长它们在实验中的寿命并简化它们的光谱特征。光谱将被分析，以获得极其准确的分子结构和内部运动的信息。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。本计划的很大一部分涉及探索新的实验方案。虽然质谱已被证明是有用的研究离子和自由基在激光光谱社区，其应用在电磁频谱的低频端仍然几乎未被探索。

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 dynamics because it is difficult to produce and trap them in the laboratory on time scales suitable for detailed experimental study. This research program combines high resolution spectroscopic techniques with ion sources and mass spectrometry to obtain rotational and vibrational spectra for a range of molecular ions and radicals. The experiments will be conducted at the University of Manitoba and the Canadian Light Source and involve a supersonic jet expansion to cool and isolate the unstable molecules. This serves to prolong their lifetime in the experiment and simplify their spectral signature. The spectra will be analyzed to obtain extremely accurate molecular structures and information about internal motions. These details are necessary to predict the chemical reactivity of molecular ions and radicals in other environments.A large portion of this program involves the exploration of novel experimental schemes. Although mass spectrometry has proven useful for studying ions and radicals in the laser spectroscopy community, its application at the low frequency end of the electromagnetic spectrum remains virtually unexplored.