Directed Self-Assemblyof Colloidal Crystals by DielectrophoreticOrdering.

In this Article, we report the dielectrophoretic assemblyof colloidalparticles and show how the kinetics of assembly and degree of orderingdepend on the particle size, charge, solution ionic strength, andfield strength and frequency. A special dielectrophoresis (DEP) samplecell is constructed and validated to quantitatively measure directedself-assembly via sequential light scattering and optical microscopymeasurements. Our results confirm the recently established scalingfor the order–disorder transition and extend it to higher scaledfrequencies. The limiting scaling of the order–disorder transitionand particle electrophoretic mobility are correctly predicted by thestandard electrokinetic model (SEKM). In particular, the order–disordertransition line is predicted from the particle properties using arecently proposed empirical scaling law and the SEKM over an orderof magnitude in particle size. [ABSTRACT FROM AUTHOR]