Electron impact partial ionization cross sections: R-carvone, 2-butanol, imidazole, and 2-nitroimidazole
Suriyaprasanth Shanmugasundaram1, Rounak Agrawal2, Dhanoj Gupta1
1Department of Physics, School of Advanced Sciences, Vellore Institute of Technology, Katpadi, Vellore 632014, Tamil Nadu, India.
The Journal of Chemical Physics
|March 6, 2024
Summary
This study calculates electron impact ionization cross sections for R-carvone, 2-butanol, imidazole, and 2-nitroimidazole. The Binary Encounter Bethe model accurately predicts these values, aiding in molecular fragment analysis.
Area of Science:
- Physical Chemistry
- Atomic and Molecular Physics
- Computational Chemistry
Background:
- Electron impact ionization is crucial for understanding molecular behavior.
- Accurate cross-section data is vital for various applications, including plasma physics and mass spectrometry.
- Limited data exists for partial ionization cross sections (PICS) of complex organic molecules.
Purpose of the Study:
- To calculate electron impact partial and total ionization cross sections (TICSs) for R-carvone, 2-butanol, imidazole, and 2-nitroimidazole.
- To validate computational methods against experimental data.
- To report novel PICS for imidazole and 2-nitroimidazole.
Main Methods:
- Utilized the Binary Encounter Bethe (BEB) model for TICS calculations.
- Employed a modified BEB method combined with mass spectrum data for PICS.
- Compared computational results with available experimental data.
Main Results:
- Calculated TICSs and PICSs for the selected molecules.
- Achieved good agreement between calculated and experimental PICS and TICS for R-carvone and 2-butanol.
- Provided the first reported PICS estimates for imidazole and 2-nitroimidazole.
Conclusions:
- The BEB model and its modified version are effective for calculating ionization cross sections.
- The modified BEB method, when combined with mass spectrum data, accurately estimates PICS.
- This study provides valuable cross-section data for molecules of interest.
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