Hierarchical Self-assembly of Atomically Precise Au Nanoclusters with Molecular Rotor-based Ligands

The hierarchical assemblies of precise nanoparticles (NPs) have created materials with emergent properties and functionalities. However, the complex assemblies remain unclear at a precise scale. Here, we show the hierarchical self-assembly of atomically precise gold nanoclusters (Au NCs) with molecular rotor-based ligands (MRL), featuring a double-layer surface. Compared to two other types of monolayer-protected (MLP) Au NCs, the significantly reduced surface density for MRL Au NCs profoundly influences their assembly behavior within the lattice. Furthermore, the long length of rotor-based ligands and the rotational freedom of the phenyl-rings of rotor-based ligands also facilitate the assembly of NCs. Our works elucidate the hierarchical assembly on a precise scale, suggesting that the rotor-based ligand's strategy offers promising potential for designing well-defined and more complex structures in supercrystals.