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Updated: Aug 6, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Interparticle interactions in nonlocal media: Attraction and repulsion from charge-polarization coupling
Ali Behjatian1, Madhavi Krishnan1,2
1Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom.
The Journal of Chemical Physics
|July 24, 2026
Summary
Standard models of charged particle interactions in liquids are incomplete. New nonlocal dielectric theory reveals electrosolvation forces, explaining phenomena like like-charged attraction and hydrophobic forces.
Area of Science:
- Physical Chemistry
- Soft Matter Physics
- Colloid Science
Background:
- Current dielectric-continuum models fail to capture complex solution-phase interactions.
- Solvent structuring at interfaces, leading to electrosolvation forces, is increasingly recognized as crucial.
- Conventional theories treat fluids as structureless media, neglecting interfacial polarization effects.
Purpose of the Study:
- To develop a theoretical framework that incorporates spatial correlations in polarization for describing solution-phase interactions.
- To investigate how nonlocal dielectric effects modify classical expectations of charged particle interactions.
- To explain phenomena such as like-charged attraction, repulsion between oppositely charged objects, and long-range hydrophobic attraction.
Main Methods:
- Employed nonlocal dielectric theory that accounts for spatial correlations in polarization.
- Developed a model where both charge and polarization govern interactions.
- Analyzed the balance between charge and polarization to predict interaction types (symmetric and antisymmetric).
Main Results:
- Demonstrated that like-charged surfaces can attract at long range and oppositely charged objects can repel.
- Showed that neutral matter can exhibit effective electrical mobility and long-range forces.
- Found that like-charged biomolecules can attract in aqueous electrolytes, and electrosolvation may explain flocculation.
Conclusions:
- Nonlocal dielectric theory provides a more accurate description of solution-phase interactions by including solvent structuring and polarization correlations.
- Electrosolvation forces play a dominant and complex role in soft matter and biological systems.
- A shift beyond traditional continuum models is necessary for a comprehensive understanding of fluid-phase physics.
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