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Alternating strings and clusters in suspensions of charged colloids
J C Everts1, M N van der Linden, A van Blaaderen
1Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands. j.c.everts@uu.nl.
Soft Matter
|July 22, 2016
Summary
Alternating strings and clusters form in charged colloid suspensions due to induced dipoles. This phenomenon, observed in binary systems, arises from electrostatic interactions and charge regulation effects.
Area of Science:
- Colloid science
- Soft matter physics
- Electrochemistry
Background:
- Charged colloidal suspensions exhibit complex phase behavior.
- Understanding particle interactions is key to predicting self-assembly.
- Double layers exceeding particle size influence interparticle forces.
Purpose of the Study:
- Investigate structure formation in binary charged colloid suspensions.
- Analyze the role of many-body and charge-regulation effects.
- Explain the mechanism behind string and cluster formation.
Main Methods:
- Utilized a binary cell model.
- Incorporated many-body and charge-regulation effects.
- Assumed constant surface potential to study two-particle interactions.
Main Results:
- Observed the formation of alternating strings and clusters.
- Identified induced dipoles near a charge-reversed state as a key factor.
- Found that effective electrostatic interactions are always repulsive in one-component systems.
Conclusions:
- Induced dipoles provide a mechanism for string and cluster formation in binary charged colloids.
- Charge regulation and many-body interactions are crucial for structure formation.
- Dumbbell and small cluster formation in one-component systems is driven by repulsion.
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