Synthesis, structures, luminescent and magnetic properties of four coordination polymers with the flexible 1,3-phenylenediacetate ligands

Abstract

Four coordination polymers, [Zn(pda)(bpy)(H 2O)] n · nH 2O ( 1), [Cd(pda)(prz)(H 2O)] n ( 2), [Co 3( μ 3-OH) 2(pda) 2(pyz)] n ·2 nH 2O ( 3) and [Pr 2(pda) 3(H 2O) 2] n ( 4) (H 2pda=1,3-phenylendiacetic acid, bpy=4,4′-bipyridine, prz=piperazine and pyz=pyrazine) have been hydrothermally synthesized and characterized. Complex 1 is a 1D wheel-like chain structure, which is further extended into a 3D metal-organic supramolecular framework by H-bonds and π– π stacking interactions. Complex 2 is a 1D ladder-like chain structure, which is also further extended into a 3D metal-organic supramolecular framework by H-bonds. Complex 3 possess a 2D sheet structure with infrequent two pairs of double-helix chains. Complex 4 features a 3D structure. Both 1 and 2 display strong blue fluorescent emission at room temperature. Magnetic susceptibility measurements of complexes 3 and 4 exhibit antiferromagnetic interactions between the nearest metal ions, with C=9.99 and 3.43 cm 3 mol −1 K, and θ=−23.9 and −46.3 K, respectively.