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Stockmayer fluid with a shifted dipole. I. Bulk behavior
Pierre J Walker1, Ananya Venkatachalam2, Samuel Varner1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
The Journal of Chemical Physics
|May 14, 2026
Summary
Shifting a Stockmayer particle's dipole disrupts local structure, reducing dielectric response and altering phase behavior. Dipole location, not just strength, controls electrostatic liquid properties.
Area of Science:
- Physical Chemistry
- Computational Physics
- Materials Science
Background:
- The effect of dipole position in Stockmayer particles on liquid properties is not fully understood.
- Geometric modifications, like dipole shifting, can significantly impact material behavior.
Purpose of the Study:
- To investigate how shifting the point dipole in Stockmayer particles affects liquid structure, dielectric response, and phase behavior.
- To provide a unified physical interpretation of these changes.
Main Methods:
- Molecular dynamics simulations
- Analytical theory
- Reparameterized co-oriented fluid functional equation
Main Results:
- Dipole shifting breaks fore-aft symmetry, altering angular structure more than radial packing.
- Reduced dielectric constant and suppressed cooperative ordering observed.
- Geometric frustration impacts vapor-liquid equilibria and ferroelectric ordering.
Conclusions:
- Dipole location is a critical control parameter in dipolar fluids.
- Geometric frustration in electrostatic liquids can be understood through structural asymmetries.
- The study offers a framework for predicting macroscopic properties from microscopic structure.
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