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Updated: May 16, 2026
06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Dissociative electron attachment to acetaldehyde, CH3CHO. A laboratory study using the velocity map imaging technique
Ewelina Szymańska1, Vaibhav S Prabhudesai, Nigel J Mason
1The Open University, Department of Physical Sciences, Walton Hall, Milton Keynes, MK7 6AA, UK.
Physical Chemistry Chemical Physics : PCCP
|December 6, 2012
Summary
This study details dissociative electron attachment to acetaldehyde, identifying key anionic products like CH3(-) and O(-). The research reveals specific dissociation pathways and fragmentation mechanisms.
Area of Science:
- * Physical Chemistry
- * Chemical Physics
- * Molecular Physics
Background:
- * Dissociative electron attachment (DEA) is a fundamental process in electron-molecule interactions.
- * Understanding DEA to organic molecules like acetaldehyde (CH3CHO) is crucial for various chemical and physical phenomena.
- * Previous studies may lack detailed insights into the specific fragmentation channels and dynamics of DEA to acetaldehyde.
Purpose of the Study:
- * To experimentally investigate the dissociative electron attachment (DEA) process in acetaldehyde (CH3CHO).
- * To identify the anionic products formed during DEA and determine their formation mechanisms.
- * To analyze the kinetic energy distributions and angular distributions of the product ions to elucidate dissociation dynamics.
Main Methods:
- * Utilized a time-of-flight spectrometer combined with the velocity slice imaging technique.
- * Investigated electron scattering resonances in acetaldehyde within the energy range of 6 to 13 eV.
- * Analyzed the kinetic energy and angular distributions of all generated anionic fragments.
Main Results:
- * Identified CH3(-), O(-), OH(-), C2H(-), C2HO(-), and CH3CO(-) as anionic products from DEA to acetaldehyde.
- * Observed that only O(-) exhibited a measurable kinetic energy distribution, indicative of a two-body dissociation.
- * CH3CO(-) showed image anisotropy, suggesting H atom ejection, while other ions indicated multi-fragmentation pathways.
Conclusions:
- * DEA to acetaldehyde proceeds through scattering resonances, yielding multiple anionic fragments.
- * The dissociation pathways vary, with O(-) formation from a direct two-body process and others from complex fragmentation.
- * The study provides detailed insights into the dynamics of electron-induced dissociation in acetaldehyde.
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