Effect of N-Donor Ligands and Metal Ions on the Coordination Polymers Based on a Semirigid Carboxylic Acid Ligand: Structures Analysis, Magnetic Properties, and Photoluminescence

Abstract

Seven novel coordination polymers derived from the 3-(3′,5′-dicarboxylphenoxy)phthalic acid (H 4 L) ligand have been constructed under similar synthesized conditions with Co(II), Zn(II), Cd(II) ions in the presence of N-donor ancillary ligands, namely, [Co 2 (HL)(4,4′-bipy)(μ 3 -OH)(μ 2 -H 2 O)] n ( 1 ), [Co 2 (L)(dpa) 2 ] n ( 2 ), {[Co 2 (L)(4,4′-bibp)(H 2 O) 4 ]·H 2 O} n ( 3 ), [Co 2 (L)(dib) 2 ] n ( 4 ), [Co 2 (L)(bix) 1.5 ] n ( 5 ), [Zn 2 (L)(bix) 1.5 ] n ( 6 ), and {[Cd 2 (L)(bix) 0.5 (H 2 O)]·2H 2 O} n ( 7 ). The various topologies of the structures have been generated by adjusting the N-donor ligands and the central metal ions. Complex 1 displays a tfz-d topology with (3,8)-connected structure, and the Schläfli symbol is (4 3 ) 2 (4 6 .6 18 .8 4 ). Complex 2 shows a 4-connected structure of sod topology with a Schläfli symbol of (4 2 .6 4 ), forming a three-dimensional (3D) 2-fold interpenetrating structure. Complex 3 presents a novel (3,3,4)-connected topology with a Schläfli symbol of (6 3 .8 3 )(6 3 )(8 3 ) and shows 2D → 3D supramolecular structure through C–H···O hydrogen bonds. Complex 4 features a four-connected structure of Nbo topology. Complex 5 and 6 are defined as the same novel (4,4,5)-connected topology with a Schläfli symbol of (4.5.6.8 3 )(4 2 .5 3 .6)(4 3 .5 3 .6 2 .7 2 ). In addition, complex 7 can be simplified as a (3,8)-connected tfz-d topology with a Schläfli symbol of (4 3 ) 2 (4 6 .6 18 .8 4 ). The contrast of 1 – 5 reveals that the ancillary ligands have key roles in adjusting the crystal structures, and the contrast of 5 – 7 indicates the central metal ions’ influences. Moreover, the magnetic properties of 1 – 5 and the fluorescence properties of 6 and 7 are discussed.