Studies on relaxation processes of core-excited molecules followed by deformation

核激发分子变形弛豫过程的研究

基本信息

批准号：
12440115
负责人：
SHIGEMASA Eiji
金额：
$ 8.77万
依托单位：
Okazaki National Research Institutes
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

This work intends to cover an important and hot topic in the research field of molecular soft X-ray spectroscopy, in which the decay dynamics following core-electron excitation as well as core-electron ionization for molecules has been extensively studied over the past two decades, which is related to the relaxation dynamics of core-excited molecules. As is widely recognized, the multi-coincidence technique is a powerful tool to investigate state-to-state dissociation dynamics following the core-hole creation. However, many experimental apparatuses previously developed for such investigations were not so close to satisfaction, because each of them has a certain limitation for its application. The new apparatus developed here is a natural enlargement of the capability of the world-famous EPICEA II developed at LURE, Orsay, France, by introducing two two-dimensional detectors with sufficiently fast response, both to electron and ion detections. A great deal of effort has been put into designing a new electrostatic analyzer with a double toroidal shape, in order to satisfy spatial focusing condition for determining the initial momenta of electrons or ions. The result of the performance tests for the analyzer performed at a newly constructed beamline BL4B of the UVSOR facility clearly indicate that further improvements are strongly desired even for the simple electron spectroscopy. The recent results obtained at LURE using a new apparatus developed with the similar concepts as we have, show directly the significant role of the molecular geometry deformation of the core-excited states in H2O and CO2, which induces to specific fragmentation channels. This kind of work is exactly what we would like to perform after the development of the present experimental setup, and gives us an impetus for future improvement of our system. A new time-of-flight mass spectrometer with a two-dimensional detector will be developed and introduced to our experimental setup in the near future.

这项工作旨在涵盖分子软X射线光谱研究领域的一个重要而热门的主题，在过去的二十年中，已经对分子的核心电子激发以及分子的核心电子电离的衰减动力学进行了广泛研究，这与核心激发动力学动力学有关。正如广泛认可的那样，多互惠技术是研究核心孔创建后的状态对状态分离动力学的强大工具。但是，许多先前用于此类研究的实验设备并不是那么接近满意度，因为它们每个人的应用都有一定的限制。这里开发的新设备是通过引入两个具有足够快速响应的二维探测器，对电子和离子探测的响应足够快，从而自然地扩大了世界举世闻名的Epicea II的能力。为了满足确定电子或离子的初始动量的空间聚焦条件，为设计具有双环形形状的新的静电分析仪已付出了很大的努力。在紫外线设施的新建的梁线BL4B上进行的分析仪的性能测试的结果清楚地表明，即使对于简单的电子光谱，也需要强烈需要进一步改进。使用与我们相似的概念开发的新设备在诱饵上获得的最新结果直接显示了H2O和CO2中核心激发状态的分子几何变形的重要作用，这诱导了特定的碎裂通道。这种工作正是我们在开发本实验设置后想要执行的，并为我们提供了将来改进系统的动力。将开发带有二维检测器的新飞行时间质谱仪，并在不久的将来将我们的实验设置介绍给我们的实验设置。