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Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Positive/negative ion velocity mapping apparatus for electron-molecule reactions
1Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, China.
The Review of Scientific Instruments
|February 4, 2012
Summary
A new compact apparatus precisely measures fragment ion angular distributions from electron-molecule reactions. This tool efficiently detects both positive and negative ions, advancing molecular reaction studies.
Area of Science:
- Atomic and Molecular Physics
- Chemical Physics
- Physical Chemistry
Background:
- Electron-molecule reactions produce charged fragments crucial for understanding chemical dynamics.
- Accurate measurement of fragment angular distributions provides insights into reaction mechanisms.
- Existing methods may lack versatility or compactness for comprehensive studies.
Purpose of the Study:
- To develop and validate a compact ion velocity mapping apparatus.
- To enable simultaneous measurement of positive and negative fragment ion angular distributions.
- To assess the apparatus's performance in electron-molecule collision and attachment studies.
Main Methods:
- Utilized a pulsed electron gun and ion velocity mapping optics.
- Employed a 2D position detector with micro-channel plates and a phosphor screen.
- Implemented a charge-coupled device camera for data acquisition.
- Achieved velocity-sliced imaging via a narrow voltage pulse on the detector.
Main Results:
- Successfully measured angular distributions for O(-) from electron attachment to NO.
- Successfully measured angular distributions for O(+) from electron collision with CO.
- Demonstrated the apparatus's capability for both positive and negative ion detection by polarity switching.
Conclusions:
- The developed compact apparatus is effective for angular distribution measurements of charged fragments.
- The system's versatility allows for the study of both electron attachment and dissociative ionization.
- This apparatus facilitates detailed investigations into electron-molecule reaction dynamics.
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