Coordination-Assembled Lanthanide-Organic Ln3L3 Sandwiches or Ln4L4 Tetrahedron: Structural Transformation and Luminescence Modulation

of main observation and conclusion Photo-functional supramolecular lanthanides assemblies have shown great potential in the materials and biomedical fields. Two new tri(tridentate) ligands (L3 and L4) highlighting small variation of the connection position to the central tridentate linkers have been designed, which leads to the emergent formation of either Ln(3)L(3)-type sandwich structures or Ln(4)L(4)-type tetrahedral cages. Moreover, nonlinear enhancement of lanthanide luminescence based on the modulation of inter-ligand charge-transfer states has been revealed on the mix-ligand Ln(3)L(3) sandwiches. Our results provide important guidance for structure-design and photoluminescence optimization of supramolecular lanthanide-organic assemblies.