Phenanthrene: Establishing Lower and Upper Bounds to the Binding Energy of a Very Weakly Bound Anion

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This work is licensed under a Creative Commons Attribution 3.0 License.

Authors

Elisabeth Gruber, University of Innsbruck
Siegfried Kollotzek, University of Innsbruck
Stefan Bergmeister, University of Innsbruck
Fabio Zappa, University of Innsbruck
Milan Ončák, University of Innsbruck
Paul Scheier, University of Innsbruck
Olof E. Echt, olof.echt@unh.eduFollow

Abstract

Quite a few molecules do not form stable anions that survive the time needed for their detection; their electron affinities (EA) are either very small or negative. How does one measure the EA if the anion cannot be observed? Or, at least, can one establish lower and upper bounds to their EA? We propose two approaches that provide lower and upper bounds. We choose the phenanthrene (Ph) molecule whose EA is controversial. Through competition between helium evaporation and electron detachment in He_nPh^- clusters, formed in helium nanodroplets, we estimate the lower bound of the vertical detachment energy (VDE) of Ph^- as about – 3 meV. In the second step, Ph is complexed with calcium whose electron affinity is just 24.55 meV. When CaPh^- ions are collided with a thermal gas of argon, one observes Ca^- product ions but no Ph^-, suggesting that the EA of Ph is below that of Ca.

Department

Physics

Publication Date

2-14-2022

Journal Title

Physical Chemistry Chemical Physics

Language

English

Publisher

Royal Society of Chemistry

Digital Object Identifier (DOI)

https://dx.doi.org/10.1039/d1cp04755h

Document Type

Article

Recommended Citation

E. Gruber, S. Kollotzek, S. Bergmeister, F. Zappa, M. Ončák, P. Scheier and O. Echt, Phys. Chem. Chem. Phys. 24 (2021) 5138-5143

Rights

Open Access, CC BY 3.0 Deed Attribution 3.0 Unported

Comments

This is an Open Access article published by Royal Society of Chemistry in Physical Chemistry Chemical Physics in 2022, available online: https://doi.org/10.1039/D1CP04755H