Lapointe Clayton P, Mason Thomas G, Smalyukh Ivan I
Department of Physics, Renewable and Sustainable Energy Institute, and Liquid Crystals Materials Research Center, University of Colorado at Boulder, Boulder, CO 80309, USA.
Science. 2009 Nov 20;326(5956):1083-6. doi: 10.1126/science.1176587.
Robust control over the positions, orientations, and assembly of nonspherical colloids may aid in the creation of new types of structured composite materials that are important from both technological and fundamental standpoints. With the use of lithographically fabricated equilateral polygonal platelets, we demonstrate that colloidal interactions and self-assembly in anisotropic nematic fluids can be effectively tailored via control over the particles' shapes. The particles disturb the uniform alignment of the surrounding nematic host, resulting in both a distinct equilibrium alignment and highly directional pair interactions. Interparticle forces between polygonal platelets exhibit either dipolar or quadrupolar symmetries, depending on whether their number of sides is odd or even, and drive the assembly of a number of ensuing self-assembled colloidal structures.
对非球形胶体的位置、取向和组装进行稳健控制，可能有助于制造新型结构化复合材料，这从技术和基础角度来看都很重要。通过使用光刻制造的等边多边形薄片，我们证明了在各向异性向列型流体中，胶体相互作用和自组装可以通过控制颗粒形状来有效调整。这些颗粒扰乱了周围向列型主体的均匀排列，导致独特的平衡排列和高度定向的成对相互作用。多边形薄片之间的颗粒间力根据其边数是奇数还是偶数，呈现出偶极或四极对称性，并驱动形成许多后续的自组装胶体结构。
