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Electron Scattering from Methyl Formate (HCOOCH3): A Joint Theoretical and Experimental Study
Natalia Tańska1, Edvaldo Bandeira2, Alessandra Souza Barbosa2
1Institute of Physics and Applied Computer Science, Faculty of Applied Physics and Mathematics, Gdańsk University of Technology, ul. Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland.
The Journal of Physical Chemistry. A
|August 29, 2023
Summary
This study investigates electron collisions with methyl formate, revealing key resonance structures in elastic and total cross sections. Findings aid understanding of molecular interactions and support theoretical models.
Area of Science:
- Chemical Physics
- Atomic and Molecular Physics
- Quantum Chemistry
Background:
- Understanding electron-molecule interactions is crucial for various chemical and physical processes.
- Methyl formate is a molecule of interest due to its presence in interstellar space and its structural similarity to formic acid.
Purpose of the Study:
- To theoretically investigate elastic low-energy electron collisions with methyl formate.
- To experimentally measure the absolute total cross section for electron scattering from methyl formate.
- To identify and characterize shape resonances in the electron scattering process.
Main Methods:
- Theoretical calculations using Schwinger multichannel and R-matrix methods.
- Experimental measurements using a 127° electron spectrometer in a linear transmission configuration.
- Analysis of integral elastic and absolute total cross sections.
Main Results:
- A π* shape resonance was observed around 1.70-1.84 eV, comparable to formic acid resonances.
- A broad structure associated with σ* shape resonances was found between 7-8 eV.
- Experimental and theoretical results showed good agreement, validated by the additivity rule.
Conclusions:
- The study successfully characterized resonances in electron scattering from methyl formate.
- Comparison with formic acid data provides insights into structure-property relationships.
- The findings contribute to a better understanding of electron-molecule dynamics and validate theoretical approaches.
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