Synthesis, structure and magnetic properties of an unusual oligonuclear iron(III)-cobalt(III) compound with oxido-, sulfato- and cyanido-bridging ligands

摘要

The synthesis, characterization, structure and magnetic properties of a hexametallic mixed-metal iron(III)-cobalt(III) compound are described. The compound has been characterized by standard spectroscopic and analytical methods to determine its composition. Single-crystal X-ray diffraction has shown that the asymmetric unit consists of discrete dinuclear dicationic units of {(mu-oxido-mu-[sulfato-O1,O2])bis[tris(2-pyridyl-methyl)amineiron(III)]}(2+), herein designated as Fe12, and two half-dinuclear dianionic units of {(mu-oxido)bis[(mu-cyanido-kappa N-pentacyanidocobaltato(III))(tris(2-pyridyl-methyl)-amine)iron(III)]}(2-) units, herein designated as Fe33a and Fe44b, generating the overall composition Co2Fe4O2(C-N)(12)(tpa)(4), 1, where tpa is tris(2-pyridyl-methyl)amine. X-ray structural results and thermogravimetric and differential scanning calorimetry measurements also indicate that the compound, depending upon its history, may contain up to nine interstitial waters of hydration, herein designated as 1(H2O)(9).