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Reactivity between non-energetic hydroxyl (OH) radicals and methane (CH4)
Emilie-Laure Zins1, Claire Pirim, Prasad Ramesh Joshi
1UPMC Univ. Paris 06, UMR 7075, Laboratoire de Dynamique, Interactions, et Réactivité, F-75005, Paris, France. emilie-laure.zins@upmc.fr
The Journal of Physical Chemistry. A
|November 30, 2012
Summary
At 3.5 K, methane reacted with hydroxyl radicals to form methyl radicals and water ice. Further reactions produced ethane (C2H6) and water ice preferentially over methanol.
Area of Science:
- Astrochemistry
- Chemical Kinetics
- Low-temperature chemistry
Background:
- Understanding interstellar ice formation and organic molecule synthesis is crucial for astrochemistry.
- Low-temperature reactions are key to simulating conditions in interstellar clouds.
Purpose of the Study:
- To investigate the reaction pathways between methane and hydroxyl radicals at cryogenic temperatures.
- To identify the primary products and reaction mechanisms under simulated interstellar conditions.
Main Methods:
- Reactions were conducted in a low-temperature (3.5 K) environment.
- Hydroxyl radicals were generated from discharged H(2)O/He mixtures.
- In situ monitoring was performed using Fourier transform infrared spectroscopy.
Main Results:
- Formation of methyl radicals (CH3) and water ice was observed simultaneously.
- Subsequent recombination reactions led to the production of ethane (C2H6).
- Ethane and water ice were formed preferentially over methanol.
Conclusions:
- The study elucidates the low-temperature reaction mechanism between methane and hydroxyl radicals.
- Results indicate preferential formation of ethane and water ice in interstellar environments.
- Findings contribute to understanding the chemical evolution of interstellar ices and organic molecules.
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