Synthesis, Crystal Structure, Magnetic Properties of a Manganese(II) Coordination Polymer with Double-Helix Chains

Abstract

A new heterocyclic carboxylate ligand, 5-(4'-pyridyl)-3-methyl-benzoic acid (Hpmba), was synthesized to construct a Mn(II) coordination polymer, namely [Mn(pmba)(2)](n) (1). Complex 1 crystallizes in monoclinic space group C2/c, with a = 17.44(2), b = 17.040(12), c = 8.680(15) angstrom, beta = 111.258(13), V = 2404(5) angstrom(3), and Z = 4. Single-crystal X-ray diffraction studies show that complex 1 has a 3D metal-organic supramolecular framework consisting of double helical chains. Magnetic studies for complex 1 show antiferromagnetic coupling between the nearest Mn( II) ions, with g = 2.11 and J = -10.1 cm(-1).