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Published on: July 19, 2019
Quasiparticle Behavior Facilitates Long-Range H+/OH- Recombination in Water
Yajuan Feng1, Chao Wang1, Wensheng Yan1
1National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui230026, China.
The Journal of Physical Chemistry Letters
|August 13, 2026
Summary
The recombination of hydronium (H3O+) and hydroxide (OH-) ions in water is clarified by advanced simulations. Long hydrogen bond networks significantly contribute to recombination, with quantum effects playing a crucial role.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Chemical Physics
Background:
- The microscopic mechanism of hydronium (H3O+) and hydroxide (OH-) ion recombination in water is poorly understood.
- This essential reaction in water involves dynamics on subnanosecond timescales and subnanometer scales.
Purpose of the Study:
- To elucidate the detailed microscopic recombination mechanism of H3O+ and OH- ions in water.
- To investigate the role of hydrogen bond networks and nuclear quantum effects (NQEs) in this process.
Main Methods:
- Molecular dynamics (MD) simulations utilizing a reactive artificial neural network potential.
- Incorporation of nuclear quantum effects (NQEs) via thermostated ring-polymer MD simulations.
Main Results:
- Long hydrogen bond wires (4-5 bonds) were found to account for approximately half of all recombination events, a previously underestimated contribution.
- The contribution of these long hydrogen bond wires increased with the inclusion of NQEs, highlighting the significance of quantum effects.
- Proton transfer across long hydrogen bond wires occurs in a quasiparticle-like manner.
Conclusions:
- A long-range recombination paradigm for water has been established.
- The study provides critical insights into the fundamental behavior and reaction mechanisms of water.
- Nuclear quantum effects significantly influence the recombination dynamics of H3O+ and OH- ions.
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