Free Radical Intermediates and Radical-Molecule Complexes Generated in Cryochemical Reactions of Fluorine and Oxygen Atoms with Guest Molecules in Free-Standing Rare Gas Crystals

犹他州大学的Charles Wight得到了实验物理化学计划和东欧计划的支持，继续研究氟和氧原子与独立稀有气体晶体中的客体分子发生低温化学反应时产生的自由基中间体和自由基分子复合物。 该项目促进了犹他州大学怀特研究小组与俄罗斯切尔诺戈洛夫卡化学物理研究所科学家之间的国际合作。 该合作方法将采用互补技术，如高分辨率EPR，FTIR和紫外光谱，以研究在低温下高度有序的大晶体中感兴趣的反应途径。 该研究预计将导致确定原子反应通道的分支比和反应产物的光化学产率，中间物种的结构和晶格位置，以及光生和扩散热原子产生的反应产物之间的区别。 研究的目标代表了与大气和燃烧化学中的当代问题有关的化学反应。 这项工作的结果预计将提供洞察长寿命的中间复合物的作用，形成附近的过渡态的化学反应。原子-分子化学反应的动力学在许多领域都很重要，包括大气化学、燃烧/火焰抑制、微电子工业中的等离子体蚀刻和化学激光。 当高能化学反应在冷晶体中进行时，可以防止反应产物像在气相反应中那样飞散。 在气相反应中不可观察的化学中间体复合物可以使用光谱方法来研究，以阐明这些重要和难以捉摸的反应物种的结构和动力学行为。

Charles Wight of the University of Utah is supported by the Experimental Physical Chemistry Program and Eastern Europe Program to continue his studies of free radical intermediates and radical-molecule complexes generated in cryochemical reactions of fluorine and oxygen atoms with guest molecules in a free-standing rare gas crystals. This project facilitates an international collaboration between Wight's research group at the University of Utah and scientists at the Institute for Chemical Physics Research at Chernogolovka, Russia. The collaborative approach will employ complementary techniques such as high-resolution EPR, FTIR, and ultraviolet spectroscopy to investigate the reaction pathways of interest in highly ordered large crystals at cryogenic temperatures. The research is expected to lead to the determination of branching ratios for reaction channels of atoms and photochemical yields of reaction products, the structure and lattice sites of intermediate species, and distinctions between reaction products arising from photogenerated and diffusing thermal atoms. The targets of the studies represent chemical reactions that are relevant to contemporary problems in atmospheric and combustion chemistry. The outcomes from this effort are expected to provide insights into the role of long-lived intermediate complexes that are formed near to the transition state of chemical reactions. The dynamics of atom-molecule chemical reactions is important in a variety of areas, including atmospheric chemistry, combustion/flaming suppression, plasma etching in the microelectronics industry, and chemical lasers. When energetic chemical reactions are performed in cold crystals, reaction products are prevented from flying apart as they do in gas phase reactions. Chemical intermediate complexes that are not observable in gas phase reactions can then be studied using spectroscopic approaches to elucidate the structure and kinetic behavior of these important and elusive reactive species.