Skip to Main content Skip to Navigation
Journal articles

Aromatic Formation Promoted by Ion-Driven Radical Pathways in EUV Photochemical Experiments Simulating Titan’s Atmospheric Chemistry

Abstract : In the atmosphere of Titan, Saturn’s main satellite, molecular growth is initiated by 85.6 nm extreme ultraviolet (EUV) photons triggering a chemistry with charged and free-radical species. However, the respective contribution of these species to the complexification of matter is far from being known. This work presents a chemical analysis in order to contribute to a better understanding of aromatic formation pathways. A gas mixture of N2/CH4 (90/10%) within the closed SURFACAT reactor was irradiated at a relatively low pressure (0.1 mbar) and room temperature for 6 h by EUV photons (∼85.6 nm). The neutral molecules formed at the end of the irradiation were condensed in a cryogenic trap and analyzed by electron ionization mass spectrometry. An analysis of the dominant chemical pathways highlights the identification of benzene and toluene and underlies the importance of small ion and radical reactions. On the basis of the experimental results, a speculative mechanism based on sequential H-elimination/CH3-addition reactions is proposed for the growth of aromatics in Titan’s atmosphere. Elementary reactions to be studied are given to instill future updates of photochemical models of Titan’s atmosphere.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03201041
Contributor : Catherine Cardon <>
Submitted on : Tuesday, May 18, 2021 - 11:02:53 AM
Last modification on : Wednesday, September 8, 2021 - 1:50:31 PM

File

Bourgalais_Aromatic formation....
Files produced by the author(s)

Identifiers

Citation

Jérémy Bourgalais, Nathalie Carrasco, Ludovic Vettier, Antoine Comby, Dominique Descamps, et al.. Aromatic Formation Promoted by Ion-Driven Radical Pathways in EUV Photochemical Experiments Simulating Titan’s Atmospheric Chemistry. Journal of Physical Chemistry A, American Chemical Society, 2021, 125 (15), pp.3159-3168. ⟨10.1021/acs.jpca.1c00324⟩. ⟨insu-03201041⟩

Share

Metrics

Record views

150

Files downloads

109