Synthesis, crystal structure and magnetic properties of poly[[diaqua{μ6-2-[bis(carboxylatomethyl)amino]terephthalato}dicobalt(II)] 1.6-hydrate]

Abstract

The asymmetric unit of the polymeric title compound {[Co2(C12H7NO8)(H2O)2]·1.6H2O}n comprises two CoII ions, which are coordinated by fully deprotonated 2-aminodiacetic terephthalic acid (adtp4–) and terminal water molecules in distorted octahedral N1O5 and O6 coordination environments. The title compound features tetranuclear CoII units bridged by κ3O:O:O′- and κ3O:O,O′-carboxylate groups, which are joined into ribbons via syn–anti carboxylate bridges. The parallel adtp4– ligands with an alternately reversed arrangement further link adjacent CoII ribbons into (010) layers, which are assembled into a three-dimensional supramolecular network via intermolecular hydrogen bonds. The disordered water solvent molecules are situated in channels parallel to [100]. Magnetic measurements and analyses reveal that the title compound displays antiferromagnetic behaviour. The purity of the title compound was characterized by X-ray powder diffraction.

Keywords

• crystal structure
• 2-aminodiacetic terephthalic acid
• tetranuclear coii units
• layered structure