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arXiv · 2408.12435

Site- and Energy-Selective Low-Energy Electron Emission by X-Rays in Aqueous Phase

Dana Bloß·Rémi Dupuy·Florian Trinter·Isaak Unger·Noelle Walsh·Gunnar Öhrwall·Niklas Golchert·Gabriel Klassen·Adrian Krone·Yusaku Terao·Johannes H. Viehmann·Lasse Wülfing·Clemens Richter·Tillmann Buttersack·Lorenz S. Cederbaum·Uwe Hergenhahn·Olle Björneholm·Arno Ehresmann·Andreas Hans
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Abstract

Low-energy-electron emission from resonant Auger final states via intermolecular Coulombic decay (RA-ICD) has been previously described as a promising scenario for controlling radiation damage for medical purposes, but has so far only been observed in prototypical atomic and molecular van der Waals dimers and clusters. Here, we report the experimental observation of RA-ICD in aqueous solution. We show that for solvated Ca$^{2+}$ ions, the emission can be very efficiently controlled by tuning the photon energy of exciting X-rays to inner-shell resonances of the ions. Our results provide the next step from proving RA-ICD in relatively simple prototype systems to understanding the relevance and potential applications of ICD in real-life scenarios.

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Dana Bloß, Rémi Dupuy, Florian Trinter, Isaak Unger, Noelle Walsh, Gunnar Öhrwall, Niklas Golchert, Gabriel Klassen, Adrian Krone, Yusaku Terao, Johannes H. Viehmann, Lasse Wülfing, Clemens Richter, Tillmann Buttersack, Lorenz S. Cederbaum, Uwe Hergenhahn, Olle Björneholm, Arno Ehresmann, Andreas Hans. 2024-08-22. Site- and Energy-Selective Low-Energy Electron Emission by X-Rays in Aqueous Phase. https://arxiv.org/abs/2408.12435

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