One novel 3D tetranuclear cadmium coordination polymer based on 2,3′,4,5′-biphenyltetracarboxylic acid: Synthesis, crystal structure and luminescence

One novel 3D cadmium coordination polymer, namely, {[Cd-2(bptc(4-))(ox(2-))(0.5)(H2O)(2)]center dot 4.5H(2)O)(n) (1), has been hydrothermally synthesized through a reaction of 2,3',4,5'-biphenyltetracarboxylic add (H4bptc) with divalent cadmium salt in the presence of a second ligand (ox = oxalic acid). X-ray single crystal structure analysis reveals that tetranuclear cadmium dusters are formed by linking two Cd1 and two Cd2 ions with carboxyl groups. Each ox2 ligand, with a bidentate chelating mode, connects two Cd2 ions from two adjacent tetranuclear clusters to afford 1D zigzag cadmium cluster chains. Furthermore, 1D chains are connected by bptc(4-) ligands to extend a 3D framework with one-dimensional channels along the [001] direction. From a topology view, complex 1 exhibits an unprecedented 2-nodal 4, 10-connected net with the Schlafli symbol of (4(6))(2)[4(9).5(12).6(22),7(2-)] J The luminescence analyses reveal that complex 1 shows an emission maximum at 437 nm, which may be attributed to the intraligand transition. A red shift of 31 nm compared with H4bptc ligand was observed and the luminescent decay lifetime is 2.74 ns, which indicates that it might be a potential blue light-emitting candidate. In addition, it was also characterized by elemental, IR spectra, PXRD and TG analyses. (C) 2015 Elsevier B.V. All rights reserved.