Muangnapoh Kullachate, Avendaño Carlos, Escobedo Fernando A, Liddell Watson Chekesha M
Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
Soft Matter. 2014 Dec 28;10(48):9729-38. doi: 10.1039/c4sm01895h. Epub 2014 Nov 4.
Colloidal aperiodic phases (i.e., entropy stabilized degenerate crystals, DCs) are realized via self-assembly of hollow fluorescent silica dimers under wedge-cell confinement. The dimer building blocks approximate two tangent spheres and their arrangements are studied via laser scanning confocal microscopy. In the DCs, the individual lobes tile a lattice and five distinct DC arrangements with square, triangular or rectangular layer symmetry are determined as a function of confinement height. Moreover, Monte Carlo simulations are used to construct the phase diagram for DCs up to two layer confinements and to analyze structural order in detail. Just as for spheres, the DC structural transitions under confinement are attributed to the ability or frustration to accommodate an integral number of particle layers between hard walls. Unlike spheres, dimers can also experience transitions involving changes in orientation. DCs are among the unconventional structures (e.g., semi-regular tilings, quasicrystals, plastic crystals) expected to enhance the properties of photonic solids.
通过楔形细胞限制下中空荧光二氧化硅二聚体的自组装实现了胶体非周期性相（即熵稳定简并晶体，DCs）。二聚体构建块近似于两个相切的球体，并通过激光扫描共聚焦显微镜研究它们的排列。在DCs中，单个叶瓣平铺成一个晶格，根据限制高度确定了具有正方形、三角形或矩形层对称性的五种不同的DC排列。此外，蒙特卡罗模拟用于构建高达两层限制的DCs相图，并详细分析结构有序性。与球体一样，限制下的DC结构转变归因于在硬壁之间容纳整数个粒子层的能力或受挫情况。与球体不同，二聚体还可以经历涉及取向变化的转变。DCs属于预期会增强光子固体性能的非常规结构（例如，半规则平铺、准晶体、塑性晶体）。
