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The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
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Long-range dipolar order and dispersion forces in polar liquids
Quinn Alexander Besford1, Andrew Joseph Christofferson2, Maoyuan Liu3
1Department of Chemical Engineering, The University of Melbourne, Victoria 3010, Australia.
The Journal of Chemical Physics
|November 23, 2017
Summary
Molecular dynamics simulations reveal unique dipolar order in polar liquids, linking structure and dispersion forces. Lifshitz theory underestimates forces in structured liquids like water, highlighting missed interactions and ion effects on solvation.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Soft Matter Physics
Background:
- Complex solvation phenomena, including specific ion effects, are crucial in polar liquids.
- Understanding these effects requires linking molecular structure and dispersion forces.
Purpose of the Study:
- To probe the structure of polar liquids using molecular dynamics.
- To investigate the relationship between dipolar order, dispersion forces, and solvation phenomena.
- To evaluate the applicability of Lifshitz theory to structured liquids and ionic solutions.
Main Methods:
- Molecular dynamics simulations were employed to analyze polar liquids.
- Specific dipolar pair correlation functions were used to probe liquid structure.
- Comparison of simulated structural order with dipolar dispersion forces and Lifshitz theory.
Main Results:
- Unique dipolar order was observed in polar liquids up to 20 Å.
- Strong agreement was found between structural order and dipolar dispersion forces.
- Lifshitz theory underestimated dispersion forces in liquids with significant local dipole correlations (e.g., water) by 5-10 times.
- Long-range order and perturbation of water structure by chloride ions were identified.
Conclusions:
- The study establishes a link between molecular structure, dispersion forces, and specific ion effects in solvation.
- Lifshitz theory requires refinement for systems with significant local dipole correlations.
- Molecular dynamics provides insights into ion-induced perturbations of liquid structure.
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