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Dissociative ionization cross sections of isobutanol
Suriyaprasanth Shanmugasundaram1, Dhanoj Gupta2
1Department of Physics, School of Advanced Sciences, Vellore Institute of Technology, Katpadi, Vellore, Tamil Nadu, 632014, India.
Scientific Reports
|November 29, 2025
Summary
This study calculates electron impact ionization cross sections for isobutanol using computational models. The findings offer valuable theoretical data for isobutanol fragments when experimental data is unavailable.
Area of Science:
- Atomic and Molecular Physics
- Chemical Physics
- Computational Chemistry
Background:
- Electron impact ionization is crucial for understanding molecular fragmentation.
- Experimental data for isobutanol ionization cross sections is limited.
- Theoretical calculations can supplement experimental findings.
Purpose of the Study:
- To calculate electron impact partial ionization cross sections (PICS) for isobutanol.
- To generate theoretical electron impact mass spectra for isobutanol and its isomers.
- To provide useful data in the absence of experimental measurements.
Main Methods:
- Utilized variants of the binary encounter Bethe model (BEB), including modified BEB (m-BEB).
- Employed the mass spectrum dependent (MSD) method for calculating PICS of cationic fragments.
- Incorporated theoretical electron impact mass spectrometry (EIMS) data from the QCxMS2 method.
Main Results:
- Calculated PICS for isobutanol fragments and compared them with data for other butanol isomers.
- Presented calculated electron impact mass spectra for isobutanol, 1-butanol, and 2-butanol.
- Validated theoretical mass spectra against experimental data where available.
Conclusions:
- The calculated PICS provide valuable theoretical data for isobutanol.
- The study offers a method for estimating theoretical PICS when experimental data is scarce.
- The computational approach aids in understanding molecular ionization processes.
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