Crystal structures from 1D to 3D: triggered by the different coordination morphologies of ligands in different reaction systems

In this report, seven new luminescent metal-organic frameworks (LMOFs), [Zn(L)(0.5)(H2O)(2)]center dot H2O (1), [Zn(L)(0.5)(DMF)] (2), [Zn-3(L)(mu(3)-OH)(2)(H2O)(4)] (3), [Zn-2(L)(DMA)(H2O)]center dot 5(H2O) (4), [Cd(L)]center dot 2(H3O)center dot(H2O) (5), [Cd-2(L)(H2O)(3)] (6), and [Pb(L)(0.5)(H2O)] (7) (H4L = [1,1':4',1 ''-terphenyl]-2',3,3 '',5'-tetracarboxylic acid; DMF = N,N-dimethylformamide; DMA = N,N-dimethylacetamide) have been solvothermally synthesized by using Zn(II), Cd(II), Pb(II) ions and H4L in different solvent systems, all of which have been routinely characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analyses show the different dimensionalities (1D, 2D or 3D) of complexes 1-7. Comparative structural studies of 1-7 reveal that the L4- ligands adopt different coordination morphologies: 1 (eta(1)mu(1)chi(1)), 2 (eta(2)mu(2)chi(2)), 3 (eta(2)mu(2)chi(2)), 4 (eta(2)mu(2)chi(2); eta(1)mu(1)chi(1)), 5 (eta(2)mu(1)chi(2)), 6 (eta(2)mu(2)chi(2); eta(2)mu(2)chi(3)), and 7 (eta(2)mu(2)chi(2); eta(2)mu(3)chi(4)) with Zn(II) (74 pm), Cd(II) (97 pm) and Pb(II) (119 pm) in different solvent systems, which produce the complexes with different frameworks. Complex 1 displays a 1D dimeric chain. Complexes 2 and 5 present a 2D layer structure with a uninodal 4-connected sql net with a symbol of (4(4).6(2)). Complexes 3, 6 and 7 have a 3D dense packing structure based on infinite 1D rod-like secondary building units (SBUs). Complex 3 is designated as a binodal (4, 6)-connected fry topological net with the point symbol (5(10).6(3).7(8))(5(4).6(2)). The whole network of 6 can be simplified as a binodal (4, 8)-connected flu topological net with a point symbol of (4(12).6(12).8(4))(4(6))(2). Complex 7 can be seen as a new binodal (5, 10)-connected topological net with the point symbol (4(10))(2)(4(28).6(16).8). Complex 4 shows a 3D framework based on a binuclear [Zn-2(CO)(3)O-3] SBU, which can be viewed as a uninodal 4-connected sra topological net with the point symbol (4(2).6(3).8). Further, the solid-state luminescence properties of the complexes were measured and studied intensively at room temperature.