Scuola Internazionale Superiore di Studi Avanzati - SISSA, via Bonomea 265, 34136 Trieste, Italy.
Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy.
Soft Matter. 2022 Nov 2;18(42):8106-8116. doi: 10.1039/d2sm00968d.
An open challenge in self-assembly is learning how to design systems that can be conditionally guided towards different target structures depending on externally-controlled conditions. Using a theoretical and numerical approach, here we discuss a minimalistic self-assembly model that can be steered towards different types of ordered constructs at the equilibrium by solely tuning a facile selection parameter, namely the density of building blocks. Metadynamics and Langevin dynamics simulations allow us to explore the behavior of the system in and out of equilibrium conditions. We show that the density-driven tunability is encoded in the pathway complexity of the system, and specifically in the competition between two different main self-assembly routes. A comprehensive set of simulations provides insight into key factors allowing to make one self-assembling pathway prevailing on the other (or ), determining the selection of the final self-assembled products. We formulate and validate a practical criterion for checking whether a specific molecular design is predisposed for such density-driven tunability of the products, thus offering a new, broader perspective to realize and harness this facile extrinsic control of conditional self-assembly.
自组装面临的一个开放性挑战是学习如何设计系统，使其能够根据外部控制条件有条件地引导至不同的目标结构。本文采用理论和数值方法，讨论了一种最小自组装模型，通过仅调整一个简单的选择参数（即构建块的密度），即可在平衡时将其引导至不同类型的有序结构。Metadynamics 和 Langevin 动力学模拟允许我们探索系统在平衡和非平衡条件下的行为。结果表明，密度驱动的可调性编码在系统的路径复杂度中，特别是在两种不同主要自组装途径之间的竞争中。全面的模拟集提供了深入了解关键因素的机会，这些因素可以使一种自组装途径在另一种途径（或 ）上占优势，从而确定最终自组装产物的选择。我们提出并验证了一种实用的标准，用于检查特定的分子设计是否容易受到产品的这种密度驱动可调性的影响，从而为实现和利用这种有条件自组装的简单外部控制提供了新的、更广泛的视角。
