Two new coordination polymers, {[Cd 2 (btc)(2,2'-bpy) 2 ]·H 2 O} n (1) and [Zn 2 (btc)(2,2'-bpy)(H 2 O)] n (2) (H 4 btc = biphenyl-2,2',4,4'-tetracarboxylic acid, 2,2'-bpy = 2,2'-bipyridine), were synthesized hydrothermally under similar conditions and characterized by elemental analysis, IR spectra, TGA, and single-crystal X-ray diffraction analysis. In complexes 1 and 2, the (btc) 4ligand acts as connectors to link metal ions to give a 2D bilayer network of 1 and a 3D metal-organic framework of 2, respec-