DMREF/Collaborative Research: Synthesis of Colloidal Crystals Guided by Particle-Based Theory and Simulation

这个设计材料来革新和设计我们的未来(DMREF)的合作研究项目将使用理论、数值模拟和实验相结合的方式来发现和合成能够制造超材料的新晶体材料。超材料具有独特的周期性结构，可以用来操纵电磁或机械能。这些材料将由悬浮液中的胶体颗粒自组装而成。这种获得超材料的途径特别灵活，因为粒子之间的多种相互作用可以被利用来形成新的晶体材料。此外，它还可以更好地控制形成过程，从而减少所产生的晶体结构中的缺陷。该项目的结果将为科学家和工程师提供改进的工具，用于识别感兴趣的胶体体系，预测稳定的晶体结构，并指导新材料的合成。理论、模拟和实验将被整合到一个程序中，以设计胶体颗粒系统，这些系统组装成所需的晶体结构。将发展新的理论和模拟方法来预测胶体体系中稳定和亚稳态的晶体结构，重点是加强经典密度泛函理论的能力和应用超平行回火模拟方法。测量和设计胶体电势以及分析晶体结构的实验工具将扩展到二元混合物。重点将放在通过使用不同的颗粒大小和材料、双峰/哑铃和Janus构型来开发和测量适合二元系统的势，以及使用先进的共聚焦显微镜技术来表征晶体结构。结果将被用于设计组装成所需晶体结构的胶体系统。需要考虑的三个具体平台是不同尺寸和相互作用势的球形粒子的二元混合物中的固-液和固-固多态转变，双重态/哑铃状粒子的塑料到紧密堆积的固体转变，以及具有取向相关吸引的粒子的非紧密堆积结构的形成(Janus)。

This Designing Materials to Revolutionize and Engineer our Future (DMREF) collaborative research project will use a combination of theory, numerical simulation, and experiment to discover and synthesize new crystalline materials that can enable the manufacturing of metamaterials. Metamaterials have unique periodic structures that can be used to manipulate electromagnetic or mechanical energy. The materials will be formed from the self-assembly of colloidal particles in suspension. This route to metamaterials is especially flexible, because many kinds of interactions among the particles can be exploited to form new crystalline materials. In addition, it allows better control over the formation process, which can reduce defects in the resulting crystalline structures. The results of the project will provide scientists and engineers with improved tools for identifying colloidal systems of interest, predicting stable crystalline structures, and guiding synthesis of the new materials. Theory, simulation, and experiments will be integrated into a program to design systems of colloidal particles that assembly into desired crystalline structures. New theoretical and simulation methods will be developed to predict stable and metastable crystal structures in colloidal systems, with a focus on enhancing capabilities of classical density functional theory and applying hyper-parallel tempering simulation methods. Experimental tools for measuring and designing colloidal potentials and analyzing crystal structures will be extended to binary mixtures. The focus will be on developing and measuring suitable potentials for binary systems through the use of different particle sizes and materials, doublets/dumbbells, and Janus configurations, and on characterizing crystal structures using advanced confocal microscopy techniques. The results will be used to design colloidal systems that assemble into desired crystalline structures. Three specific platforms to be considered are solid-fluid and solid-solid polymorphic transitions in binary mixtures of spherical particles of different size and interaction potential, plastic to close-packed solid transitions for doublet/dumbbell particles, and the formation of non-close-packed structures for particles with orientation-dependent attraction (Janus).