Synthesis, crystal structure and magnetic properties of an Iron(III) Pyridine-2,3,5,6-tetracarboxylate complex

A new pyridine-2,3,5,6-tetracarboxylato-bridged Fe(III) complex with a K+ counter ion. K[Fe(H2pdtc)2](1), was prepared from the reaction of Fe2(SO4)3 · 7H2O, pyridine-2,3,5,6-tetracarboxylic acid and KOH under ambient conditions. The complex has been characterized by single-crystal and powder X-ray diffraction, IR spectroscopy, TG analysis, elemental analyses, and magnetic measurements. Through intermolecular hydrogen bonding and π-π stacking interactions, the [Fe(H2pdtc)2]- complex anions are assembled into supramolecular double chains with the K + cations located between them. The variable temperature magnetic measurement has shown a weak ferromagnetic behavior over the range 300-10 K followed by antiferromagnetic behavior below 10 K. © 2011 Verlag der Zeitschrift für Naturforschung.