Ion Pair Imaging Spectroscopy

在这项由化学学部实验物理化学项目资助的提案中，纽约州立大学石溪分校的Arthur Suits将进行离子对成像光谱的研究项目。真空紫外线辐射将用于驱动各种分子的解离产生离子对。当一对离子中的一个是无结构的（例如氯离子）时，释放的动能以类似于光电子能谱（XPS）的方式绘制了共碎片的能级。这种方法允许对没有稳定前体的物种进行研究，并且可以很容易地实现光学无法达到的探测水平。该项目的首要目标是获得传统技术无法获得的难以捉摸的离子种类的振动频率和热化学数据。甲基阳离子的初步研究将扩展到包括相关的C2和C3物种，以及亚甲基阳离子。这些研究的结果将被用作与理论计算比较的基准，因为它们在确定所有化学所依赖的热化学尺度方面具有内在价值，并有助于发展对燃烧、大气和星际化学中重要的瞬态物质的基本理解。

In this proposal funded by the Experimental Physical Chemistry Program of the Chemistry Division, Arthur Suits of the State University of New York at Stony Brook will pursue a program of research on ion pair imaging spectroscopy. Vacuum ultraviolet radiation will be used to drive dissociation of various molecules to produce ion pairs. The kinetic energy released, when one of the ions in the pair is structureless (e.g., chloride ion) maps the energy levels of the co-fragment in a manner analogous to photoelectron spectroscopy (XPS). This approach permits study of species for which no stable precursors re available, and will readily allow for probing levels that are optically inaccessible. The overarching goal of this project is to obtain vibrational frequencies and thermochemical data for elusive ionic species not accessible to conventional techniques. Preliminary studies of the methyl cation will be extended to include related C2 and C3 species, as well as the methylene cation.The results of these studies will be used as benchmarks for comparison to theoretical calculations, for their intrinsic value in determining the thermochemical scales on which all of chemistry relies, and for developing the fundamental understanding of transient species of importance in combustion, atmospheric and interstellar chemistry.