Self-assembly and molecular recognition are critical processes both in life and material sciences. They usually depend on strong, directional non-covalent interactions to gain specificity and to make long-range organization possible. Most supramolecular constructs are also at least partially governed by topography, whose role is hard to disentangle. This makes it nearly impossible to discern the potential of shape and motion in the creation of complexity. Here, we demonstrate that long-range order in supramolecular constructs can be assisted by the topography of the individual units even in the absence of highly directional interactions. Molecular units of remarkable simplicity self-assemble in solution to give single-molecule thin two-dimensional supramolecular polymers of defined boundaries. This dramatic example spotlights the critical function that topography can have in molecular assembly and paves the path to rationally designed systems of increasing sophistication.

自组装和分子识别是生命科学和材料科学中的关键过程。它们通常依赖于强的、定向的非共价相互作用来获得特异性并使远程组织成为可能。大多数超分子结构也至少部分受地形控制，其作用很难解开。这使得几乎不可能辨别形状和运动在创造复杂性方面的潜力。在这里，我们证明了即使在没有高度定向相互作用的情况下，也可以通过单个单元的地形来辅助超分子结构中的长程有序。极其简单的分子单元在溶液中自组装形成具有限定边界的单分子薄二维超分子聚合物。