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

犹他大学的查尔斯·鬼魂得到了实验物理化学计划和东欧计划的支持，继续研究自由基中间体和自由基-分子复合体，这些自由基中间体和自由基-分子复合体是氟和氧原子与客体分子在独立的稀有气体晶体中进行低温化学反应产生的。该项目促进了鬼魂在犹他大学的研究小组与俄罗斯切尔诺戈洛夫卡化学物理研究所的科学家之间的国际合作。这种协作方法将使用诸如高分辨率EPR、FTIR和紫外光谱等补充技术来研究在低温下高度有序的大晶体的感兴趣的反应路径。这项研究有望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。这些研究的目标代表了与当代大气和燃烧化学问题相关的化学反应。这一努力的结果预计将为深入了解在化学反应过渡态附近形成的长寿命中间络合物的作用提供见解。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刻蚀和化学激光。当高能化学反应在冷晶体中进行时，反应产物不会像在气相反应中那样飞散。在气相反应中不能观察到的化学中间体化合物可以用光谱方法来研究，以阐明这些重要的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.