Hydrothermal Synthesis, Crystal Structure, and Luminescent Properties of Two Zinc(II) and Cadmium(II) 3D Metal‐Organic Frameworks

Two zinc(II) and cadmium(II) metal‐organic frameworks with mixed ligands, {[Zn 2 (biim‐4) 2 (TDC) 2 ] · 2.5H 2 O} n ( 1 ) and {[Cd 2 (biim‐4) 2 (TDC) 2 · 2H 2 O]} n ( 2 ) [biim‐4 = 1,1′‐(1,4‐butanediyl)bis(imidazole); H 2 TDC = thiophene‐2,5‐dicarboxylic acid], were hydrothermally synthesized. Both of them are characterized by elemental analysis, IR spectroscopy, and single crystal X‐ray diffraction. In 1 , the four‐connected Zn II nodes are connected by four linear ligands extending into a 3D network, which further integrates a fivefold interpenetrating diamond 3D topological network and the free water molecules distribute in void space, whereas in 2 , the Cd II ions are in a distorted octahedral arrangement linked by TDC 2– and biim‐4 ligands to construct a 3D framework. In topology analysis, C11 and C14 are simplified as 3‐connected nodes and the 3D framework displays a (3,5)‐connected net. Furthermore, the thermal and photoluminescent properties of 1 and 2 were also studied.