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Updated: Apr 24, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Linear and quadratic static response functions and structure functions in Yukawa liquids
Péter Magyar1, Zoltán Donkó2, Gabor J Kalman3
1Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, H-1121 Budapest, Konkoly-Thege Miklós Street 29-33, Hungary.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 13, 2014
Summary
We calculated density response functions for Yukawa liquids using molecular dynamics simulations and equilibrium fluctuations. Results confirm fluctuation-dissipation theorems and suggest a cluster representation for correlation functions.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Computational Physics
Background:
- Yukawa liquids are model systems relevant to various physical phenomena.
- Understanding density response functions is crucial for characterizing material properties.
- Equilibrium fluctuations and external perturbations offer complementary approaches to study systems.
Purpose of the Study:
- To compute linear and quadratic static density response functions of 3D Yukawa liquids.
- To validate the fluctuation-dissipation theorems by comparing different calculation methods.
- To investigate the relationship between three-point and two-point structure functions.
Main Methods:
- Molecular dynamics simulations with external perturbation potentials.
- Analysis of equilibrium fluctuations using static structure factors.
- Application of fluctuation-dissipation theorems.
Main Results:
- Linear and quadratic static density response functions were computed.
- Excellent agreement was found between response functions from simulations and fluctuation analysis.
- The quadratic fluctuation-dissipation theorem was confirmed.
- The three-point structure function demonstrated factorizability into two-point functions.
Conclusions:
- The study validates the fluctuation-dissipation theorems for Yukawa liquids.
- A cluster representation for equilibrium triplet correlation functions is proposed.
- The findings provide insights into the statistical mechanics of dense liquids.
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