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Spontaneous phase separation of materials is a powerful strategy to generate highly defined 2D nanomorphologies with novel properties and functions. Exemplary are such morphologies in block copolymers or amphiphilic systems, whose formation can be well predicted based on parameters such as volume fraction and shape factor. In contrast, the formation of 2D nanomorphologies is currently unpredictable in materials perfectly defined at the molecular level, in which crystallinity plays a significant role. Here, we introduce a crystal lattice analysis to predict a priori the formation of 2D nanomorphologies from the crystalline units in phase-separated soft materials. We show that the formation of lamellar morphologies, their domain spacings, and thermal transition temperatures of such materials can be predicted using a straightforward crystal lattice analysis workflow. We envision this approach to facilitate the design and discovery of new materials with 2D nanomorphologies that are essential for next-generation electronic applications.

Amplification of asymmetry in complex molecular systems results from a delicate interplay of chiral supramolecular structures and their chemical reactivity. In this work, we show how the helicity of supramolecular assemblies can be controlled by performing a non-stereoselective methylation reaction on comonomers. By methylating chiral glutamic acid side chains in benzene-1,3,5-tricarboxamide (BTA) derivatives to form methyl esters, the assembly properties are modulated. As reacted comonomers, the methyl ester-BTAs induce a stronger bias in the screw-sense of helical fibers predominantly composed of stacked achiral alkyl-BTA monomers. Hence, applying the in situ methylation in a system with the glutamic acid-BTA comonomer induces asymmetry amplification. Moreover, mixing small quantities of enantiomers of glutamic acid-BTA and glutamate methyl ester-BTA in the presence of the achiral alkyl-BTAs leads to deracemization and inversion of the helical structures in solution via the in situ reaction toward a thermodynamic equilibrium. Theoretical modeling suggests that the observed effects are caused by enhanced comonomer interactions after the chemical modification. Our presented methodology enables on-demand control over asymmetry in ordered functional supramolecular materials.