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06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
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Multiple Electron Ejection from Proteins Resulting from Single-Photon Excitation in the Valence Shell
Rodolphe Antoine1,2, Quentin Enjalbert1,2, Luke MacAleese1,2
1†Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex, France.
The Journal of Physical Chemistry Letters
|August 14, 2015
Summary
Protein polyanions exhibit multielectron photodetachment below 20 eV, revealing significant electronic correlations. These multiradical polyanions are surprisingly stable, with implications for radiobiology.
Area of Science:
- Atomic and Molecular Physics
- Chemical Physics
- Biophysics
Background:
- One-photon multiple ionization reveals electron correlations in atoms and molecules.
- The Auger process involves core-shell ionization and subsequent electron emission.
- Coulombic attraction typically hinders multielectron emission from molecular ions.
Purpose of the Study:
- Investigate multielectron photodetachment from protein polyanions.
- Explore the role of electronic correlations in proteins.
- Assess the stability of resulting multiradical polyanions.
Main Methods:
- Utilized vacuum ultraviolet synchrotron radiation for excitation.
- Employed a radiofrequency ion trap for protein polyanion studies.
- Analyzed photodetachment yielding double, triple, and quadruple electron emissions.
Main Results:
- Observed multielectron emissions (double, triple, quadruple) from protein polyanions.
- Ionization thresholds were found to be below 20 eV photon energy.
- Indicated large electronic correlations between weakly bound electrons in proteins.
Conclusions:
- Protein polyanions facilitate multielectron photodetachment due to overcome Coulombic attraction.
- Protein polyanions exhibit significant electronic correlations.
- The resulting multiradical polyanions demonstrate remarkable stability, relevant to radiobiology.
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