Deexcitation dynamics of superhydrogenated polycyclic aromatic hydrocarbon cations after soft-x-ray absorption

Journal article (2014)

Authors

G Reitsma Zernike Institute for Advanced Materials
Leon Boschman Rijksuniversiteit Groningen
M. J. Deuzeman University Medical Center Groningen
O. González-Magaña University Medical Center Groningen
S. Hoekstra Van Swinderen Institute, University Medical Center Groningen
S.M. Cazaux Rijksuniversiteit Groningen
R. Hoekstra University Medical Center Groningen, Zernike Institute for Advanced Materials
Thomas Schlathölter University Medical Center Groningen
Affiliation
External organisation
More Info
expand_more

Published Date

2014

Language

English

Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Affiliation

External organisation

Abstract

We have investigated the response of superhydrogenated gas-phase coronene cations upon soft x-ray absorption. Carbon (1s) transitions were resonantly excited at hν=285eV. The resulting core hole is then filled in an Auger decay process, with the excess energy being released in the form of an Auger electron. Predominantly highly excited dications are thus formed, which cool down by hydrogen emission. In superhydrogenated systems, the additional H atoms act as a buffer, quenching loss of native H atoms and molecular fragmentation. Dissociation and transition state energies for several H loss channels were computed by means of density functional theory. Using these energies as input into an Arrhenius-type cascade model, very good agreement with the experimental data is found. The results have important implications for the survival of polyaromatic hydrocarbons in the interstellar medium and reflect key aspects of graphene hydrogenation.