Phase behavior of Janus colloids determined by sedimentation equilibrium
Daniel J Beltran-Villegas1, Benjamin A Schultz, Nguyen H P Nguyen
1Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA. beltran@umich.edu rlarson@umich.edu.
Soft Matter
|April 5, 2014
Summary
We explored particle phase behavior using simulation, revealing distinct lamellar, fluid, and rotator phases for single-patch Janus particles. This method rapidly assesses equations of state and phase diagrams.
Area of Science:
- Soft Matter Physics
- Computational Materials Science
Background:
- Understanding particle interactions is crucial for designing novel materials.
- Janus particles, with distinct surface properties, offer unique self-assembly possibilities.
Purpose of the Study:
- To investigate the phase behavior of short-range interacting isotropic and single-patch Janus particles.
- To develop and validate a simulation method for rapid assessment of equations of state and phase behavior.
Main Methods:
- Simulations of sedimentation equilibrium were employed.
- The methodology was validated against traditional simulation techniques for isotropic particles.
Main Results:
- The simulation method accurately predicted phase behavior for isotropic interactions.
- For single-patch Janus particles (area coverage > ~0.63), a lamellar phase, a fluid phase, and a rotator close-packed structure were observed.
- An interplay between translational and orientational order was identified.
Conclusions:
- The study successfully applied sedimentation equilibrium simulations to analyze particle phase behavior.
- The observed lamellar phase exhibits a different stability range compared to previous simulations of similar systems.
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