@article{f6786f8e204a41d38301694b396bf4bf,
title = "Dissociation and radiative stabilization of the indene cation: The nature of the C–H bond and astrochemical implications",
abstract = "Indene (C9H8) is the only polycyclic pure hydrocarbon identified in the interstellar medium to date, with an observed abundance orders of magnitude higher than predicted by astrochemical models. The dissociation and radiative stabilization of vibrationally hot indene cations are investigated by measuring the time-dependent neutral particle emission rate from ions in a cryogenic ion-beam storage ring for up to 100 ms. Time-resolved measurements of the kinetic energy released upon hydrogen atom loss from C9H8+, analyzed in view of a model of tunneling through a potential energy barrier, provide the dissociation rate coefficient. Master equation simulations of the dissociation in competition with vibrational and electronic radiative cooling reproduce the measured dissociation rate. We find that radiative stabilization arrests one of the main C9H8 destruction channels included in astrochemical models, helping to rationalize its high observed abundance.",
author = "Stockett, {M. H.} and A. Subramani and C. Liu and Marlton, {S. J. P.} and Ashworth, {E. K.} and H. Cederquist and H. Zettergren and Bull, {J. N.}",
note = "DATA AVAILABILITY: The data that support the findings of this study are available from the corresponding author upon reasonable request. FUNDING: This work was supported by Swedish Research Council Grant Nos. 2023-03833 (H.C.) and 2020-03437 (H.Z.), Knut and Alice Wallenberg Foundation Grant No. 2018.0028 (H.C. and H.Z.), EPSRC Grant No. EP/W018691 (J.N.B.), Olle Engkvist Foundation Grant No. 200-575 (M.H.S.), and Swedish Foundation for International Collaboration in Research and Higher Education (STINT) Grant No. PT2017-7328 (J.N.B. and M.H.S.). We acknowledge the DESIREE infrastructure for provisioning of facilities and experimental support and thank the operators and technical staff for their invaluable assistance. The DESIREE infrastructure receives funding from the Swedish Research Council under the Grant Nos. 2021-00155 and 2023-00170. This article is based upon work from COST Action CA21126—carbon molecular nanostructures in space (NanoSpace), supported by COST (European Cooperation in Science and Technology).",
year = "2025",
month = may,
day = "13",
doi = "10.1063/5.0257874",
language = "English",
volume = "162",
journal = "The Journal of Chemical Physics",
issn = "0021-9606",
publisher = "American Institute of Physics",
number = "18",
}