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Updated: Jul 31, 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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Intermediate-range order governs dynamics in dense colloidal liquids
Navneet Singh1, Zhen Zhang2, A K Sood3,4
1Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India.
Summary
Liquids possess surprising intermediate-range order, not just nearest-neighbor structure. This order correlates with dynamical heterogeneities, impacting liquid relaxation dynamics.
Area of Science:
- Soft Matter Physics
- Colloidal Science
- Materials Science
Background:
- Conventional view: liquids lack structure beyond nearest neighbors.
- Emerging evidence: liquid microstructure is rich and functionally important.
- Existing methods: often system-specific or lack physical intuition.
Purpose of the Study:
- To uncover and characterize the intermediate-range order in bidisperse colloidal liquids.
- To link this structure to the system's dynamics and relaxation properties.
- To provide a physically intuitive framework for understanding liquid structure-dynamics relationships.
Main Methods:
- Single-particle resolved three-dimensional confocal microscopy.
- Application of a novel four-point correlation function.
- Quantification of particle-level dynamics.
Main Results:
- Bidisperse colloidal liquids exhibit nontrivial structure with alternating icosahedral and dodecahedral layers.
- This order extends beyond nearest-neighbor distances and increases with supercooling.
- Intermediate-range order, not short-range order, directly correlates with dynamical heterogeneities.
Conclusions:
- Established a direct link between intermediate-range liquid structure and dynamics.
- Demonstrated the critical role of order beyond nearest neighbors in liquid behavior.
- Opened new avenues for investigating structure-property relationships in diverse liquid systems.
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