Display Settings:

Format

Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
J Chem Phys. 2009 Apr 21;130(15):154901. doi: 10.1063/1.3115641.

Simple models for two-dimensional tunable colloidal crystals in rotating ac electric fields.

Author information

  • 1School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom.

Abstract

We compare the behavior of a new two-dimensional aqueous colloidal model system with a simple numerical treatment. To the first order the attractive interaction between the colloids induced by an in-plane rotating ac electric field is dipolar, while the charge stabilization leads to a shorter ranged, Yukawa-like repulsion. In the crystal-like "rafts" formed at sufficient field strengths, we find quantitative agreement between experiment and Monte Carlo simulation, except in the case of strongly interacting systems, where the well depth of the effective potential exceeds 250 times the thermal energy. The "lattice constant" of the crystal-like raft is located approximately at the minimum of the effective potential, resulting from the sum of the Yukawa and dipolar interactions. The experimental system has display applications, owing to the possibility of tuning the lattice spacing with the external electric field. Limitations in the applied field strength and relative range of the electrostatic interactions of the particles result in a reduction in tunable lattice spacing for small and large particles, respectively. The optimal particle size for maximizing the lattice spacing tunability was found to be around 1000 nm.

PMID:
19388766
[PubMed]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for American Institute of Physics
    Loading ...
    Write to the Help Desk