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Uracil-DNA Glycosylase Assay by Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry Analysis
Published on: April 22, 2022
Low-energy electron collisions with gas-phase uracil
1A. A. Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125, USA.
The Journal of Chemical Physics
|November 15, 2006
Summary
We studied electron collisions with uracil molecules to understand resonance structures. Findings reveal pi* shape resonances and a potential sigma* resonance, impacting electron scattering and dissociative attachment.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Electron Scattering
Background:
- Uracil is a fundamental biomolecule with significant implications in biological processes.
- Understanding electron-uracil interactions is crucial for fields like radiation chemistry and astrobiology.
- Resonance structures in electron scattering significantly influence molecular interactions and fragmentation pathways.
Purpose of the Study:
- To investigate the resonance structure of the electron-uracil scattering cross section.
- To identify and characterize potential shape resonances (pi* and sigma*) in electron-uracil collisions.
- To correlate elastic scattering resonances with observed features in dissociative attachment.
Main Methods:
- Symmetry-resolved calculations for elastic electron scattering.
- Utilized fixed-nuclei, static-exchange, and static-exchange-plus-polarization approximations.
- Performed electron-impact excitation calculations for low-lying triplet and singlet electronic states.
Main Results:
- Located expected pi* shape resonances in the electron-uracil scattering cross section.
- Indicated the possible existence of a low-energy sigma* resonance.
- Observed a very large cross section for singlet electron-impact excitation.
Conclusions:
- The identified resonances provide insights into the electron-uracil interaction mechanism.
- Resonance structures correlate with features observed in electron-induced dissociative attachment.
- This study enhances the understanding of electron-driven processes in uracil.
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