Decoding the spectroscopic features and time scales of aqueous proton defects
Abstract
Acid solutions demonstrate a variety of complex structural and dynamical features arising from the presence of multiple interacting reactive proton defects and counterions. Yet, disentangling the transient structural motifs of proton defects in the water hydrogen bond network and the mechanisms for their interconversion remains a formidable challenge. In this work, we use simulations treating the quantum nature of both the electrons and nuclei to show how the experimentally observed spectroscopic features and relaxation time scales can be elucidated using a physically transparent coordinate that encodes the overall asymmetry of the solvation environment of the proton defect. We demonstrate that this coordinate can be used both to discriminate the extremities of the features observed in the linear vibrational spectrum and to explain the molecular motions that give rise to the interconversion time scales observed in recent nonlinear experiments. This analysis provides a unified condensed-phase picture of the proton structure and dynamics that, at its extrema, encompasses proton sharing and spectroscopic features resembling the limiting Eigen [H3O(H2O)3]+ and Zundel [H(H2O)2]+ gas-phase structures, while also describing the rich variety of interconverting environments in the liquid phase.
- Authors:
-
- Stanford Univ., CA (United States)
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC); Univ. of California, Oakland, CA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC); National Science Foundation (NSF)
- OSTI Identifier:
- 1543857
- Grant/Contract Number:
- AC02-05CH11231
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Chemical Physics
- Additional Journal Information:
- Journal Volume: 148; Journal Issue: 22; Journal ID: ISSN 0021-9606
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Citation Formats
Napoli, Joseph A., Marsalek, Ondrej, and Markland, Thomas E. Decoding the spectroscopic features and time scales of aqueous proton defects. United States: N. p., 2018.
Web. doi:10.1063/1.5023704.
Napoli, Joseph A., Marsalek, Ondrej, & Markland, Thomas E. Decoding the spectroscopic features and time scales of aqueous proton defects. United States. doi:10.1063/1.5023704.
Napoli, Joseph A., Marsalek, Ondrej, and Markland, Thomas E. Mon .
"Decoding the spectroscopic features and time scales of aqueous proton defects". United States. doi:10.1063/1.5023704. https://www.osti.gov/servlets/purl/1543857.
@article{osti_1543857,
title = {Decoding the spectroscopic features and time scales of aqueous proton defects},
author = {Napoli, Joseph A. and Marsalek, Ondrej and Markland, Thomas E.},
abstractNote = {Acid solutions demonstrate a variety of complex structural and dynamical features arising from the presence of multiple interacting reactive proton defects and counterions. Yet, disentangling the transient structural motifs of proton defects in the water hydrogen bond network and the mechanisms for their interconversion remains a formidable challenge. In this work, we use simulations treating the quantum nature of both the electrons and nuclei to show how the experimentally observed spectroscopic features and relaxation time scales can be elucidated using a physically transparent coordinate that encodes the overall asymmetry of the solvation environment of the proton defect. We demonstrate that this coordinate can be used both to discriminate the extremities of the features observed in the linear vibrational spectrum and to explain the molecular motions that give rise to the interconversion time scales observed in recent nonlinear experiments. This analysis provides a unified condensed-phase picture of the proton structure and dynamics that, at its extrema, encompasses proton sharing and spectroscopic features resembling the limiting Eigen [H3O(H2O)3]+ and Zundel [H(H2O)2]+ gas-phase structures, while also describing the rich variety of interconverting environments in the liquid phase.},
doi = {10.1063/1.5023704},
journal = {Journal of Chemical Physics},
number = 22,
volume = 148,
place = {United States},
year = {2018},
month = {4}
}
Web of Science
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Works referencing / citing this record:
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