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arXiv · 2412.02206

Measurements and simulations of rate coefficients for the deuterated forms of the H2 + + H2 and H3 + + H2 reactive systems at low temperature

Miguel Jiménez-Redondo·Olli Sipilä·Pavol Jusko·Paola Caselli
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Abstract

The rate coefficients of various isotopic variations of the H2+ + H2 and H3+ + H2 reactions in the 10-250 K temperature range were measured using a cryogenic 22 pole radio frequency ion trap. The processes involving diatomic ions were found to behave close to the Langevin rate, whereas temperature-dependent rate coefficients were obtained for the four isotopic exchange processes with triatomic ions. Fitting the experimental data using a chemical code allowed us in specific cases to constrain rate coefficients that were not directly measured in the ion trap. The reported rate coefficients suggest a more efficient hydrogenation of deuterated H3+ forms than usually assumed in astrochemical models, which might affect deuteration rates in warmer environments.

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Miguel Jiménez-Redondo, Olli Sipilä, Pavol Jusko, Paola Caselli. 2024-12-03. Measurements and simulations of rate coefficients for the deuterated forms of the H2 + + H2 and H3 + + H2 reactive systems at low temperature. https://doi.org/10.1051/0004-6361%2F202451757

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