Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
Phys Rev Lett. 2012 Dec 28;109(26):265506. doi: 10.1103/PhysRevLett.109.265506.
Theories of phase change and self-assembly often invoke the idea of a "quasiequilibrium," a regime in which the nonequilibrium association of building blocks results nonetheless in a structure whose properties are determined solely by an underlying free energy landscape. Here we study a prototypical example of multicomponent self-assembly, a one-dimensional fiber grown from red and blue blocks. We find that if the equilibrium structure possesses compositional correlations different from those characteristic of random mixing, then it cannot be generated without error at any finite growth rate: there is no quasiequilibrium regime. However, by exploiting dynamic scaling, structures characteristic of equilibrium at one point in phase space can be generated, without error, arbitrarily far from equilibrium. Our results, supported by mean-field theory in higher dimensions, thus suggest a "nonperturbative" strategy for multicomponent self-assembly in which the target structure is, by design, not the equilibrium one.
相变和自组装理论常常涉及到“准平衡”的概念，即尽管非平衡的构建块的缔合会导致结构的形成，但结构的性质仅由潜在的自由能景观决定。在这里，我们研究了一个多组分自组装的典型例子，即由红色和蓝色块组成的一维纤维。我们发现，如果平衡结构具有与随机混合不同的组成相关性，那么在任何有限的生长速率下，它都不能无错误地生成：不存在准平衡状态。然而，通过利用动态标度，我们可以在远离平衡的任意远处，无错误地生成在相空间的一个点上具有平衡特征的结构。我们的结果得到了更高维度的平均场理论的支持，因此提出了一种用于多组分自组装的“非微扰”策略，其中目标结构不是平衡结构。
