Centre de Recherche Paul-Pascal, CNRS & Université de Bordeaux, 115 Avenue Schweitzer, 33600, Pessac, France.
Nat Commun. 2018 Apr 11;9(1):1405. doi: 10.1038/s41467-018-03745-4.
Chirality plays an important role in science from enantiomeric separation in chemistry to chiral plasmonics in nanotechnology. However, the understanding of chirality amplification from chiral building blocks to ordered helical superstructures remains a challenge. Here, we demonstrate that topological defects, such as screw dislocations, can drive the chirality transfer from particle to supramolecular structure level during the crystallization process. By using a model system of chiral particles, which enables direct imaging of single particle incorporation into growing crystals, we show that the crystallization kinetic pathway is the key parameter for monitoring, via the defects, the chirality amplification of the crystalline structures from racemic to predominantly homohelical. We provide an explanation based on the interplay between geometrical frustration, racemization induced by thermal fluctuations, and particle chirality. Our results demonstrate that screw dislocations not only promote the growth, but also control the chiral morphology and therefore the functionality of crystalline states.
手性在科学中起着重要的作用，从化学中的对映体分离到纳米技术中的手性等离子体。然而，从手性构建块到有序螺旋超结构的手性放大的理解仍然是一个挑战。在这里，我们证明了拓扑缺陷，如螺旋位错，可以在结晶过程中驱动手性从颗粒到超分子结构水平的传递。通过使用手性颗粒的模型体系，我们可以直接观察到单个颗粒掺入生长晶体的情况，我们表明结晶动力学途径是通过缺陷监测晶体结构从外消旋到手性同型螺旋的关键参数。我们基于几何阻挫、热波动引起的外消旋和颗粒手性之间的相互作用提供了一个解释。我们的结果表明，螺旋位错不仅促进了生长，而且控制了晶体的手性形态，从而控制了晶体状态的功能。
