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Updated: Nov 30, 2025
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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Correlated atomic dynamics in liquid seen in real space and time
Takeshi Egami1, Yuya Shinohara2
1Department of Materials Science and Engineering, and Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA.
The Journal of Chemical Physics
|November 14, 2020
Summary
Liquid structure is dynamic, not static. We propose using the distinct Van Hove function to capture atomic correlations in space and time, improving our understanding of liquid dynamics and transport properties.
Area of Science:
- Condensed matter physics
- Physical chemistry
- Materials science
Background:
- Characterizing liquid dynamics is challenging due to similar timescales for structure, diffusion, and phonons (around a picosecond).
- The concept of instantaneous liquid structure may be insufficient for describing inherently dynamic systems.
Purpose of the Study:
- To advocate for a dynamic description of liquid structure using the distinct part of the Van Hove function.
- To explore how atomic correlations influence liquid transport properties.
Main Methods:
- Utilizing inelastic neutron and X-ray scattering measurements.
- Employing computational simulations.
- Analyzing the distinct part of the Van Hove function to depict space-time atomic correlations.
Main Results:
- The distinct Van Hove function reveals dynamic correlations between atoms.
- Strong atomic correlations were observed in liquids like water.
- These correlations impact fluid transport properties such as viscosity and diffusivity.
Conclusions:
- The distinct Van Hove function provides a more comprehensive description of liquid structure and dynamics.
- Understanding atomic correlations is crucial for predicting transport properties in liquids.
- This approach offers a refined perspective on liquid characterization.
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