Two New Tetranuclear Cluster-based Coordination Polymers based on Isomorphic Semi-rigid Tetracarboxylate Ligands: Syntheses, Structures, and Luminescent Properties

Two new tetranuclear cluster-based compounds, namely [Cd-2(L1)(H2O)(DMA)](n)(1) and [Cd2Ba2(L2)(H2O)(6)(DMA)](n)(2) [H(4)L1 = 3-(3',5'-dicarboxylphenoxy) phthalic acid, H(4)L2 = 6-(3',4'-dicarboxyl-phenoxy) isophthalic acid, DMA =N,N'-dimethylacetamide], were successfully synthesized under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analyses. Compound1features a two-dimensional (2D) layered framework with tetranuclear [Cd-4(COO)(6)] clusters as building subunits, and can be simplified into a binodal (3, 6)-connectedkgdtopological network with the schlafli symbol of {4(3)}(2){4(6);6(6);8(3)}, and compound2features a three-dimensional (3D) complicated framework based on heterometallic tetranulear [Cd2Ba2(COO)(8)] cluster subunits, and can be simplified into a binodal (3, 6)-connected topological network. In addition, compounds1and2not only have high thermal stabilities but also show strong luminescent emissions at room temperature.