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Analysis of Volatile and Oxidation Sensitive Compounds Using a Cold Inlet System and Electron Impact Mass Spectrometry
Published on: September 5, 2014
Electron scattering by trimethylene oxide, c-(CH2)3O, molecules
Czesław Szmytkowski1, Alicja Domaracka, Paweł Mozejko
1Atomic Physics Group, Faculty of Applied Physics and Mathematics, Gdańsk University of Technology, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland. czsz@mif.pg.gda.pl
The Journal of Chemical Physics
|April 10, 2009
Summary
Electron scattering cross sections were measured for trimethylene oxide. Results show energy-dependent trends and agree with theoretical calculations, aiding in understanding cyclic ether properties.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Chemical Physics
Background:
- Electron-scattering cross sections are fundamental properties for understanding molecular interactions.
- Trimethylene oxide, a cyclic ether, presents an interesting case for studying electron-molecule collisions due to its unique structure.
Purpose of the Study:
- To experimentally and theoretically determine electron-scattering cross sections for trimethylene oxide.
- To compare the electron scattering behavior of trimethylene oxide with its isomers and related cyclic ethers.
- To develop a predictive model for electron scattering cross sections in cyclic ethers.
Main Methods:
- Absolute total cross section (TCS) measured using a linear electron-transmission method from 1 to 400 eV.
- Integral elastic cross section (ECS) and ionization cross section (ICS) calculated using the additivity rule approximation and binary-encounter-Bethe approach up to 3 keV.
- Comparison with experimental data for acetone and other cyclic ethers (n=2-4).
Main Results:
- TCS generally decreases with energy, with discernible resonant-like structures between 3-10 eV.
- The sum of calculated ECS and ICS shows good agreement with the measured TCS.
- A consistent trend was observed for cyclic ethers, where TCS can be represented as a sum of contributions from methylene groups and oxygen atoms.
- Predicted TCS for cyclopentamethylene oxide based on this additive model.
Conclusions:
- The study provides comprehensive electron-scattering data for trimethylene oxide.
- The additive model effectively predicts cross sections for cyclic ethers, facilitating studies of larger molecules.
- Findings contribute to a deeper understanding of electron-molecule interactions in cyclic organic compounds.
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