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Zero-Point-Energy Driven Isotopic Exchange of the [H₃O]^- anion Probed by Mid-Infrared Action Spectroscopy.

ABSTRACT: We present the first observation of vibrational transitions in the [H₃O]^- anion, an intermediate in the anion-molecule reaction of water, H₂O, and hydride, H^-, using a laser-induced isotopic H/D exchange reaction action spectroscopy scheme applied to anions. The observed bands are assigned as the fundamental and first overtone of the H₂O-H^- vibrational stretching mode, based on anharmonic calculations within the vibrational perturbation theory and vibrational configuration interaction. Although the D₂O·D^- species has the lowest energy, our experiments confirm the D₂O·H^- isotope to be a sink of the H/D exchange reaction. Ab initio calculations corroborate that the formation of D₂O·H^- is favored, as the zero-point-energy difference is larger between D₂ and H₂ than between D₂O·H^- and D₂O·D^-.

SUBMITTER: Dinu DF

PROVIDER: S-EPMC11311240 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Zero-Point-Energy Driven Isotopic Exchange of the [H3O]- anion Probed by Mid-Infrared Action Spectroscopy.

Dinu Dennis F DF Ončák Milan M Thorwirth Sven S Liedl Klaus R KR Brünken Sandra S Schlemmer Stephan S Jusko Pavol P

Journal of the American Chemical Society 20240724 31

We present the first observation of vibrational transitions in the [H3O]- anion, an intermediate in the anion-molecule reaction of water, H2O, and hydride, H-, using a laser-induced isotopic H/D exchange reaction action spectroscopy scheme applied to anions. The observed bands are assigned as the fundamental and first overtone of the H2O-H- vibrational stretching mode, based on anharmonic calculations within the vibrational pertur ...[more]

PMID: 39049192

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