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Updated: Jul 20, 2026
06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
High resolution dissociative electron attachment to gas phase adenine
D Huber1, M Beikircher, S Denifl
1Institut für Ionenphysik und Angewandte Physik and Center for Molecular Biosciences, Leopold Franzens Universität Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria.
The Journal of Chemical Physics
|September 13, 2006
Summary
This study investigates electron attachment to adenine, discovering new negative ions and comparing anion yields with total cross-section measurements. Results show good agreement for adenine but notable differences for thymine.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Molecular Physics
Background:
- Nucleobases are fundamental components of DNA and RNA.
- Understanding their electronic properties is crucial for molecular biology and radiation chemistry.
- Dissociative electron attachment (DEA) is a key process in low-energy electron interactions with molecules.
Purpose of the Study:
- To investigate the dissociative electron attachment to gas-phase adenine.
- To identify and characterize fragment anions formed during DEA.
- To compare experimental results with existing data and explore differences in related molecules.
Main Methods:
- Utilized a double focusing sector field mass spectrometer for high-resolution mass analysis and relative ion yield measurements.
- Employed a hemispherical electron monochromator for high-resolution electron energy measurements.
- Measured negative ion mass spectra at specific electron energies (2 and 6 eV) and ion efficiency curves over an energy range of 0-15 eV.
Main Results:
- Discovered several new negative ions in the mass spectra of adenine, differing from previous gas-phase studies.
- Observed good agreement between the total anion yield (sum of fragment anions) and independently measured total cross-sections for negative ion formation in adenine.
- Noted peculiar differences when comparing adenine and thymine regarding the shape of cross-section curves, despite good agreement for adenine.
Conclusions:
- The study provides a detailed characterization of negative ion formation in adenine via DEA.
- The findings validate the experimental approach and highlight the sensitivity of DEA to molecular structure.
- Further investigation is warranted to understand the observed discrepancies between adenine and thymine.
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