| Abstract
| - This paper describes the two-dimensional self-assembly of hexagonal plates at the interface betweenperfluorodecalin and water. The plates were prepared with five different permutations of hydrophobic andhydrophilic faces. The shapes and amplitudes of the menisci that form on the faces of the plates determinethe magnitude of the lateral capillary forces through which they interact. The amplitudes of the meniscialso influencethrough their out-of-plane componentsthe position and orientation of the plate relativeto the plane of the liquid−liquid interface. In these experiments, the plates were made of poly(dimethylsiloxane) (PDMS) (ρ = 1.05 g/cm3) containing aluminum oxide (ρ = 4.00 g/cm3); this dopantadjusted the density of the plates, the extent to which they sank into the liquid−liquid interface, and thusthe structure of their menisci. The plates studied had densities of 1.05 to 1.86 g/cm3. This work complementsprevious papers (Bowden, N.; Choi I. S.; Grzybowski, B. A.; Whitesides, G. M. J. Am. Chem. Soc.1999,121, 5373. Bowden, N.; Oliver, S. R. J.; Whitesides, G. M. J. Phys. Chem. B2000, 104, 2714.) that examinedthe assembly of hexagonal plates with densities at the extremes of the range studied. By following thestructures of the aggregates formed at intermediate densities, it is possible to observe the way in whichthe self-assembling system transitions from an aggregate of one structure to that of another. The resultsfrom these studies are relevant to the design of micrometer-sized plates capable of self-assembly.
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