Structural, magnetic and theoretical study of mononuclear nickel(II) and cobalt(II) compounds of a benzimidazole thiobutanoic acid derivative

摘要

A structural, magnetic and theoretical study of the mononuclear octahedral cobalt(II) and nickel(II) coordination compounds with the tridentate ligand, 4-(benzimidazol-2-yl)-3-thiabutanoic acid (Hbztb), was performed. At low temperature, both compounds present weak antiferromagnetic couplings via intermolecular interactions. In the [Co(bztb)(2)]center dot H2O compound, intermolecular hydrogen bonding between the benzimidazolic nitrogen atom and the neighboring carboxylic oxygen contribute to the magnetic pathway for the coupling between the cobalt(II) mononuclear complexes. Whereas in [Ni(bztb)(2)]center dot 3H(2)O, two nickel(II) compounds are linked by non-covalent interactions through water molecules, [(Ni(bztb)(2) center dot center dot center dot (H2O)(3)center dot center dot center dot Ni(bztb)(2)], which play an important role on the super-exchange magnetic coupling contributing to the magnetic MO. The magnetic behavior of both coordination compounds was analyzed by DFT theoretical calculations. (C) 2014 Elsevier B. V. All rights reserved.