Geometrical manipulation of complex supramolecular tessellations by hierarchical assembly of amphiphilic platinum(II) complexes

Significance Despite numerous studies on the supramolecular engineering of intricate self-assembled patterns via noncovalent intermolecular interactions, it is still challenging to overcome the geometric and topological frustrations for creating complex tessellations by using geometrically simple building motifs. This work demonstrates a semi-regular rhombitrihexagonal Archimedean tiling enabled by hierarchical assembly of C2h-symmetric platinum(II) amphiphiles in the bulk. Based on this finding, the rational design of introducing symmetry lowering into supramolecular tiling is achieved by coassembly strategies. The current study provides promising possibilities for the construction of complex supramolecular architectures and an in-depth understanding into the structural order and molecular organization in soft materials. Here we report complex supramolecular tessellations achieved by the directed self-assembly of amphiphilic platinum(II) complexes. Despite the twofold symmetry, these geometrically simple molecules exhibit complicated structural hierarchy in a columnar manner. A possible key to such an order increase is the topological transition into circular trimers, which are noncovalently interlocked by metal···metal and π–π interactions, thereby allowing for cofacial stacking in a prismatic assembly. Another key to success is to use the immiscibility of the tailored hydrophobic and hydrophilic sidechains. Their phase separation leads to the formation of columnar crystalline nanostructures homogeneously oriented on the substrate, featuring an unusual geometry analogous to a rhombitrihexagonal Archimedean tiling. Furthermore, symmetry lowering of regular motifs by design results in an orthorhombic lattice obtained by the coassembly of two different platinum(II) amphiphiles. These findings illustrate the potentials of supramolecular engineering in creating complex self-assembled architectures of soft materials.