Syntheses, Crystal Structures, and Magnetic Properties of Manganese(II) and Cobalt(II) Complexes with 4-Hydroxypyridine-2, 6-dicarboxylic Acid

Two complexes, namely [Mn3(hpda)2(H2O)8]n (1) and [Co3(hpdaH)3(H2O)7]·(4, 4′py)·(H2O)3 (2) (hpdaH3 = 4-hydroxypyridine-2, 6-dicarboxylic acid) were synthesized under hydrothermal conditions and were characterized by elemental analysis, IR spectrocopy, and X-ray diffraction. Complex 1 forms a 1D linear chain, which is extended by hydrogen bonds resulting in a 3D network. Complex 2 consists of a trinuclear cobalt(II) unit, which is further linked by hydrogen bonds to form a 3D supramolecular network. Magnetic measurements show that there is a weak antiferromagnetic interaction between the adjacent MnII ions in 1.