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Microfluidic Pneumatic Cages: A Novel Approach for In-chip Crystal Trapping, Manipulation and Controlled Chemical Treatment
Published on: July 12, 2016
Self-diffusion of particles in complex fluids: temporary cages and permanent barriers
Markus Bier1, René van Roij, Marjolein Dijkstra
1Institute for Theoretical Physics, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, The Netherlands. m.bier@uu.nl
Physical Review Letters
|December 31, 2008
Summary
We studied self-diffusion in complex fluids using dynamic density functional theory. Our findings reveal non-Gaussian motion in liquid crystals due to particle cages and barriers, matching experimental results.
Area of Science:
- Complex fluids
- Liquid crystals
- Statistical mechanics
Background:
- Self-diffusion is crucial for understanding fluid dynamics.
- Previous models often neglect background fluctuations.
- Complex fluids exhibit unique diffusion behaviors.
Purpose of the Study:
- To investigate self-diffusion in complex fluids.
- To incorporate background fluctuations into dynamic density functional theory.
- To analyze diffusion in nematic and smectic liquid crystals.
Main Methods:
- Dynamic density functional theory (DDFT)
- Explicitly accounting for fluctuating background fields
- Application to nematic and smectic liquid crystal systems
Main Results:
- Identified competition between temporary cages and permanent barriers.
- Observed non-Gaussian diffusive motion.
- Found correlated diffusion across different directions.
- Demonstrated qualitative agreement with experimental data.
Conclusions:
- Explicitly modeling time-dependent self-consistent molecular fields is essential.
- Background fluctuations significantly impact self-diffusion in complex fluids.
- The developed DDFT formalism accurately captures observed phenomena.
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