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Updated: Jun 27, 2026
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The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
Electric Field Pushes the Water Dimer Radical Cation toward the Hemibonded Structure
Aoyun Qu1, Zhexuan Song1, Pengbo Gao1
1Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China.
The Journal of Physical Chemistry Letters
|June 25, 2026
Summary
Electric fields significantly alter the water dimer radical cation
Area of Science:
- Physical Chemistry
- Quantum Chemistry
- Chemical Physics
Background:
- The water dimer radical cation ((H2O)2+•) is crucial in ionized water chemistry.
- It exists in hydrogen-bonded ([H3O+···OH•]) and hemibonded ([H2O···OH2]+•) forms.
- External electric fields (EFs) may influence these conformations.
Purpose of the Study:
- Investigate the impact of electric fields on water dimer radical cation stability and interconversion.
- Explore how EFs affect the hydrogen-bonded and hemibonded forms.
- Understand EF-driven chemistry in microdroplets and catalysis.
Main Methods:
- Accurate quantum-chemical calculations using CCSD(T).
- Multireference CASPT2 calculations for open-shell systems under EFs.
- Analysis of energetics, structure, and vibrational signatures in response to EFs.
Main Results:
- Positive EFs stabilize the hydrogen-bonded form; negative EFs destabilize it, inducing proton transfer.
- Both positive and negative EFs stabilize the hemibonded form and transition state.
- Negative EFs significantly lower the interconversion barrier between forms, enabling barrierless conversion.
Conclusions:
- Intense electric fields can promote hemibond stabilization in water dimer radical cations.
- EFs provide mechanistic insights into water cation chemistry in microdroplets.
- Results offer understanding for EF-assisted catalysis and radiation chemistry.
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