论文标题
用于分层自组装的胶体簇中的磁耦合
Magnetic coupling in colloidal clusters for hierarchical self-assembly
论文作者
论文摘要
操纵胶体颗粒自组织的方式是功能软材料设计的核心挑战。应对这一挑战需要使用以高度特定方式相互作用的构建块。但是,它们的制造受到可用合成程序的复杂性的限制。在这里,我们证明,从实验可用的磁性胶体开始,我们可以使用简单的可扩展过程创建适合层次自我组织的各种复杂的构建块。使用计算机模拟,我们在球形限制中压缩球形和立方磁胶体,并研究其适合形成具有可再现的结构和磁性特性的小簇。我们发现,尽管这些簇的结构高度可重复,但它们的磁性取决于粒子的形状。只有球形颗粒具有产生一致的磁性构型的旋转自由度,而三次颗粒会使簇能的最小化感到沮丧,从而导致各种磁性构型。为了强调它们进行自组装的潜力,我们证明了三个磁性颗粒的簇已经形成高度非平凡的阿基米德晶格,即交错的kagome,bounce和honeycomb,当查看同一单层结构的不同方面时。此处介绍的工作在概念上提供了一种不同的方式来设计材料,通过利用可以容易自我组织成复杂结构的预组装磁性构建块来设计材料。
Manipulating the way in which colloidal particles self-organise is a central challenge in the design of functional soft materials. Meeting this challenge requires the use of building blocks that interact with one another in a highly specific manner. Their fabrication, however, is limited by the complexity of the available synthesis procedures. Here, we demonstrate that, starting from experimentally available magnetic colloids, we can create a variety of complex building blocks suitable for hierarchical self-organisation using a simple scalable process. Using computer simulations, we compress spherical and cubic magnetic colloids in spherical confinement, and investigate their suitability to form small clusters with reproducible structural and magnetic properties. We find that, while the structure of these clusters is highly reproducible, their magnetic character depends on the particle shape. Only spherical particles have the rotational degrees of freedom to produce consistent magnetic configurations, whereas cubic particles frustrate the minimisation of the cluster energy, resulting in various magnetic configurations. To highlight their potential for self-assembly, we demonstrate that already clusters of three magnetic particles form highly nontrivial Archimedean lattices, namely staggered kagome, bounce and honeycomb, when viewing different aspects of the same monolayer structure. The work presented here offers a conceptually different way to design materials by utilizing pre-assembled magnetic building blocks that can readily self-organise into complex structures.