Three Novel Lanthanide Metal-Organic Frameworks (Ln-MOFs) Constructed by Unsymmetrical Aromatic Dicarboxylatic Tectonics: Synthesis, Crystal Structures and Luminescent Properties

Three novel Ln(III)-based coordination polymers, {[Ln(2) (2,4-bpda)(3) (H(2)O)(x)]·yH(2)O}(n) (Ln = La (III) (1), x = 2, y = 0, Ce (III) (2), Pr (III) (3), x = 4, y = 1) (2,4-H(2)bpda = benzophenone-2,4-dicarboxylic acid) have been prepared via a solvothermal method and characterized by elemental analysis, IR, and single-crystal X-ray diffraction techniques. Complex 1 exhibits a 3D complicated framework with a new 2-nodal (3,7)-connected (4(2)·5) (4(4)·5(1)·6(6)·8) topology. Complexes 2 and 3 are isomorphous, and feature a 3D 4-connected (6(5)·8)-CdSO(4) network. Moreover, solid-state properties such as thermal stabilities and luminescent properties of 1 and 2 were also investigated. Complex 1 crystallized in a monoclinic space group P2(1)/c with a = 14.800 (3), b = 14.500 (3), c = 18.800 (4) Å, β = 91.00 (3), V = 4033.9 (14) Å(3) and Z = 4. Complex 2 crystallized in a monoclinic space group Cc with a = 13.5432 (4), b = 12.9981 (4), c = 25.7567 (11) Å, β = 104.028 (4), V = 1374.16 (7) Å(3) and Z = 4.