Giant Truncated Metallo-Tetrahedron with Unexpected Supramolecular Aggregation Induced Emission Enhancement

The artificial synthesis of giant, three-dimensional and shell-like architectures with growing complexity and novel func-tionalities is an especially challenging task for chemists. Fullerenes and self-assembled cages are remarkable examples that are proved milestones in the field of functional materials. Herein, we present another unique system: a giant terpyr-idine-based truncated metallo-tetrahedral architecture that includes dense-packed ionic pairs with a significant internal cavity. This huge metallo-tetrahedron with a molecular weight up to 70,000 Da was self-assembled simultaneously with 64 components: 12 large antler-shaped ligands (5), 4 star-shaped ligands (6) and 48 Cd2+ ions. Surprisingly, the giant tetrahedron shows broad visible emission (400-640 nm) and the aggregation induced emission enhancement (AIEE) via hierarchical assembly into highly ordered nano-aggregates. Tunable emission color and near white-light emission in mixed solvent systems were also achieved. The present work not only affords an effective approach to the creation of giant shell-like architectures that can be used to mimic biological viruses and chemical frameworks but also provides a new class of functional metallo-architectures.