Three-dimensional imaging of molecular orbitals by the electron-electron-ion coincidence experiment

通过电子-电子-离子符合实验对分子轨道进行三维成像

基本信息

批准号：
11640494
负责人：
TAKAHASHI Masahiko
金额：
$ 2.24万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

Electron momentum spectroscopy (EMS) allows us to measure molecular orbital pattern. It. consists of a high-energy electron-impact ionization experiment in which kinematics of all the electrons are fully determined with coincident detection of the two outgoing electrons. While a variety of molecular orbitals have been widely studied by EMS, the resulting information is limited only to the radial part of wavefunction due to randomly oriented target molecules. This project has aimed to develop a new method, based on EMS, for looking at three-dimensional orbital patterns by further coincident detection of fragment-ion.Within the period of the present grant-in-aid the following attempts have been made.1. An electronic circuit and a fragment-ton detector have been constructed. By combining these with the present EMS spectrometer an apparatus for this project has been completed.2. Coincidence experiments for inelastically scattered electrons and fragment-tons, which are generated by the elec … More tron-impact inner-shell excitation, have been carried out for nitrogen molecule. While coincidence signal has been successfully detected, the statistics is not good. This observation indicates that the imaging technique is best suited for fragment-ion detection in this project.3. Angular correlations between photoelectrons and fragment-ions have been studied for several diatomic molecules. From comparison of experiments and theory it has been found that most of valence-shell ionization transitions are followed by the fast ion dissociation processes, and can be used for this project.4. A new EMS apparatus has been constructed, where for the two outgoing electrons two position-sensitive detectors are employed. Their ability of simultaneous energy- and angle-dispersive measurements gives rise to considerable improvement in data gathering speed.Application of the imaging technique to fragment-ion detection as well as the electrons are under consideration in order to raise the methodology here to become brand-new spectroscopy for orbital pattern imaging. Less

电子动量光谱（EMS）使我们能够测量分子轨道模式。它。由高能电子电离实验组成，在该实验中，所有电子的运动学都通过对两个传出电子的重合检测完全确定。尽管EMS已广泛研究了各种分子轨道，但由于随机取向靶分子，所得信息仅限于波函数的径向部分。该项目旨在通过EMS开发一种新方法，以通过对片段离子的进一步检测来查看三维轨道模式。在当前授予的时期，已经进行了以下尝试。1。已经构建了电子电路和碎片量检测器。通过将它们与当前的EMS光谱仪相结合，该项目的设备已完成。2。由Elec产生的无弹性电子和碎片吨的巧合实验已经用于氮分子进行。尽管已经成功地检测到了巧合信号，但统计数据不好。该观察结果表明，成像技术最适合该项目中的片段离子检测。3。光电子与碎片离子之间的角相关性已经研究了几个双原子分子。从实验和理论的比较中，已经发现大多数价壳电离转变之后是快速离子解离过程，并且可以用于该项目4。已经构建了一种新的EMS设备，用于两个传出电子的两个位置敏感探测器。它们的简单能量和角度分散性测量的能力会导致数据收集速度的显着提高。将成像技术应用于碎片离子检测以及电子设备正在考虑，以提高此处的方法，以成为轨道图案成像的全新光谱。较少的