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The impact of water vapor on the OH reactivity toward CH₃CHO at ultra-low temperatures (21.7-135.0 K): Experiments and theory.

ABSTRACT: The role of water vapor (H₂O) and its hydrogen-bonded complexes in the gas-phase reactivity of organic compounds with hydroxyl (OH) radicals has been the subject of many recent studies. Contradictory effects have been reported at temperatures between 200 and 400 K. For the OH + acetaldehyde reaction, a slight catalytic effect of H₂O was previously reported at temperatures between 60 and 118 K. In this work, we used Laval nozzle expansions to reinvestigate the impact of H₂O on the OH-reactivity with acetaldehyde between 21.7 and 135.0 K. The results of this comprehensive study demonstrate that water, instead, slows down the reaction by factors of ∼3 (21.7 K) and ∼2 (36.2-89.5 K), and almost no effect of added H₂O was observed at 135.0 K.

SUBMITTER: Neeman EM

PROVIDER: S-EPMC7611909 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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The impact of water vapor on the OH reactivity toward CH3CHO at ultra-low temperatures (21.7-135.0 K): Experiments and theory.

Neeman E M EM González D D Blázquez S S Ballesteros B B Canosa A A Antiñolo M M Vereecken L L Albaladejo J J Jiménez E E

The Journal of chemical physics 20210701 3

The role of water vapor (H2O) and its hydrogen-bonded complexes in the gas-phase reactivity of organic compounds with hydroxyl (OH) radicals has been the subject of many recent studies. Contradictory effects have been reported at temperatures between 200 and 400 K. For the OH + acetaldehyde reaction, a slight catalytic effect of H2O was previously reported at temperatures between 60 and 118 K. In this work, we used Laval nozzle expansions to reinvestigate the impact of H<su ...[more]

PMID: 34293904

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