Impact of N-donor auxiliary ligands on three new Co(ii)-based coordination polymers with symmetrical tetracarboxylate ligands: a magnetism study

Abstract

Three new Co(II)-based coordination polymers, namely [Co(L)]_n (1), [Co(H₂L)_1.5(1,10-phen)(H₂O)₂]_n (2), and {[Co₂(L)(dpa)(H₂O)₂]·(H₄L)_0.5}_n (3) (H₄L = 5,5′-(ethene-1,2-diyl)diisophthalic acid, 1,10-phen = 1,10-phenanthroline, dpa = (E)-1,2-di(pyridin-4-yl)diazene), were solvothermally synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, and magnetic studies. 1 and 3 display a 3D framework with (4,6)-connected CrB-type topology, and 2 displays a 1D chain built by the unprotonated H₂L linker. The magnetic studies indicated that CPs 1–3 show the presence of weak antiferromagnetic interactions within the Co(II) units.