A Hybrid Open-Framework Iron Phosphate-Oxalate with a Large Unidimensional Channel, Showing Reversible Hydration

A novel inorganic-organic hybrid iron phosphate-oxalate material has been synthesized hydrothermally in the presence of ethylenediamine as the structure-directing agent. The three-dimensional solid possesses neutral iron phosphate layers built up by strictly alternating FeO ₆ octahedra and PO ₄ tetrahedra creating large voids of ~5 Å free diameter bound by 12 T atoms (T = Fe, P). The oxalate units act as pillars holding the layers apart, and together. The positions of the oxalate units and the amine are such as to give rise to a large one-dimensional channel. The solid orders antiferromagnetically with a Neel temperature of 31 K. The solid undergoes reversible dehydration and shows adsorptive properties.