Self-assembly of supramolecular monomers into 2D twinned crystals on mica surface

Despite the widespread use of microscopy techniques to characterize supramolecular polymers, the role of surfaces in the formation of these structures is unclear. Here we describe the epitaxial growth of intriguing 2D crystals of alkyl benzene-1,3,5-triscarboxamides formed by competitive attractive interactions with the mica surface. In contrast to the fibrous structure observed in apolar diluted solution, five-fold twinned crystals or ribbon-like structures are obtained on the mica surface. Moreover, these structures are still dynamic on the surface, being able to reorganize during the atomic force microscopy measurements. This work demonstrates that surface-monomer interactions can be exploited to modulate the structure of 1D supramolecular polymers into 2D crystals.