Four new coordination polymers constructed using 2,2′-oxybis(benzoic acid) and auxiliary N-donor ligands: Syntheses, structures, magnetic behavior and DFT studies

The flexible dicarboxylate ligands can be employed in transitional metal M(II) ions (M = Cu, Co and Ni)/aromatic chelate ligand/linear ligand systems to generate 0D, 1D chain to 2D networks polymers. compound 1 is 0D structure, compound 2 is a 1D helical chain structure, compound 3 displays a 2D wavy layer with the paddle-wheel SBUs and compound 4 features a 2-fold interpenetrating 3D structure with 2D brick-wall networks. Moreover, magnetic properties of compounds 1, 2 and 4 have also been investigated. According to the crystal structures, the DFT-BS approach was applied to study the magnetic coupling behavior for compounds 1, 2 and 4, the result reveals that the calculated exchange coupling constants J were in good agreement with the experimental data.