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Colloidal hard-sphere crystal growth frustrated by large spherical impurities
Volkert W A de Villeneuve1, Roel P A Dullens, Dirk G A L Aarts
1Van't Hoff Laboratory, Debye Research Institute, University of Utrecht, Padualaan 8, 3584 CH Utrecht, Netherlands.
Science (New York, N.Y.)
|August 20, 2005
Summary
Large impurities disrupt colloid crystal growth. Smaller impurities cause greater growth inhibition due to local crystal frustration, impacting crystal structure and formation.
Area of Science:
- Colloid science
- Materials science
- Crystallization
Background:
- Impurities significantly influence crystal nucleation, growth, and final structure.
- Understanding impurity effects is crucial for controlling crystallization processes.
Purpose of the Study:
- To investigate the impact of large, spherical polymethylmethacrylate (PMMA) impurities on the crystal growth of PMMA colloids.
- To analyze how impurity size affects crystal growth dynamics and structure.
Main Methods:
- Utilized monodisperse, hard PMMA colloids in a density- and optically matching apolar solvent.
- Employed laser scanning confocal microscopy to image 2D slices of crystal growth around impurities.
- Observed crystal growth initiated from the sample bottom.
Main Results:
- Impurities acted as centers for grain boundaries, with a persistent fluid particle layer surrounding them.
- Crystal growth rate was highly sensitive to the size of the impurity.
- Smaller impurities exhibited a more pronounced inhibition of crystal growth, indicating local crystal frustration.
Conclusions:
- The curvature of impurities, particularly smaller ones, induces local crystal frustration, significantly affecting colloid crystal growth.
- Impurity size is a critical parameter controlling the extent of crystal growth inhibition and structural defects.
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