Das Avishek, Limmer David T
Department of Chemistry, University of California, Berkeley, CA 94720.
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720.
Proc Natl Acad Sci U S A. 2023 Oct 3;120(40):e2217242120. doi: 10.1073/pnas.2217242120. Epub 2023 Sep 25.
We use a nonequilibrium variational principle to optimize the steady-state, shear-induced interconversion of self-assembled nanoclusters of DNA-coated colloids. Employing this principle within a stochastic optimization algorithm allows us to identify design strategies for functional materials. We find that far-from-equilibrium shear flow can significantly enhance the flux between specific colloidal states by decoupling trade-offs between stability and reactivity required by systems in equilibrium. For isolated nanoclusters, we find nonequilibrium strategies for amplifying transition rates by coupling a given reaction coordinate to the background shear flow. We also find that shear flow can be made to selectively break detailed balance and maximize probability currents by coupling orientational degrees of freedom to conformational transitions. For a microphase consisting of many nanoclusters, we study the flux of colloids hopping between clusters. We find that a shear flow can amplify the flux without a proportional compromise on the microphase structure. This approach provides a general means of uncovering design principles for nanoscale, autonomous, functional materials driven far from equilibrium.
我们使用非平衡变分原理来优化DNA包覆胶体自组装纳米团簇的稳态、剪切诱导的相互转化。在随机优化算法中应用这一原理，使我们能够确定功能材料的设计策略。我们发现，远离平衡的剪切流可以通过解耦平衡系统所需的稳定性和反应性之间的权衡，显著提高特定胶体状态之间的通量。对于孤立的纳米团簇，我们发现了通过将给定的反应坐标与背景剪切流耦合来放大跃迁速率的非平衡策略。我们还发现，通过将取向自由度与构象转变耦合，剪切流可以有选择地打破细致平衡并最大化概率流。对于由许多纳米团簇组成的微相，我们研究了团簇之间胶体跳跃的通量。我们发现，剪切流可以放大通量，而不会对微相结构造成成比例的损害。这种方法提供了一种通用手段，用于揭示远离平衡驱动的纳米级、自主、功能材料的设计原理。
