Abstract
Inner-shell ionization of an isolated atom typically leads to Auger decay. In an environment, for example, a liquid or a van der Waals bonded system, this process will be modified, and becomes part of a complex cascade of relaxation steps. Understanding these steps is important, as they determine the production of slow electrons and singly charged radicals, the most abundant products in radiation chemistry. In this communication, we present experimental evidence for a so-far unobserved, but potentially very important step in such relaxation cascades: Multiply charged ionic states after Auger decay may partially be neutralized by electron transfer, simultaneously evoking the creation of a low-energy free electron (electron transfer-mediated decay). This process is effective even after Auger decay into the dicationic ground state. In our experiment, we observe the decay of Ne2+ produced after Ne 1s photoionization in Ne–Kr mixed clusters.
Highlights
Inner-shell ionization of an isolated atom typically leads to Auger decay
In 1997, Cederbaum et al.[4] predicted another pathway to produce a low-energy electron in a loosely bound system: If an ion in such system is produced in an excited state, it may transit to a lower electronic state, while simultaneously a low-energy electron is emitted from a neighbouring atom or molecule. This interatomic/intermolecular Coulombic decay process (ICD) has since been the topic of both theoretical[5] and experimental[6] studies, and it was shown to be an important source of slow electrons in water[7,8]
We discuss in detail how these extra electrons are produced in the Ne–Kr mixed clusters (Fig. 4)
Summary
Inner-shell ionization of an isolated atom typically leads to Auger decay. In an environment, for example, a liquid or a van der Waals bonded system, this process will be modified, and becomes part of a complex cascade of relaxation steps. In 1997, Cederbaum et al.[4] predicted another pathway to produce a low-energy electron in a loosely bound system: If an ion in such system is produced in an excited state, it may transit to a lower electronic state, while simultaneously a low-energy electron is emitted from a neighbouring atom or molecule This interatomic/intermolecular Coulombic decay process (ICD) has since been the topic of both theoretical[5] and experimental[6] studies, and it was shown to be an important source of slow electrons in water[7,8]. As both slow electrons and reactive radicals are produced in such Auger-ICD cascades, their relevance for radiation damage and radiation therapy was suggested[12,13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
