The structure of iron dextran cores

Mossbauer spectroscopy and Rietveld refinement of x-ray powder diffraction data have been used to determine the structure of the iron-based cores of a freeze dried iron dextran complex. The x-ray powder diffraction data show that the cores are essentially akaganeite (β-FeOOH) with a monoclinic crystal structure (space group I2/m) with cell dimensions of a = 10.594(4) A, b = 3.019(1) A, c = 10.299(3) A and β = 88.98(5)°. In agreement with other reports there is evidence of chlorine on some of the origin sites. There are two non-equivalent Fe sites in the structure, each of which is surrounded by a distorted octahedron of oxygen atoms. These results are consistent with the Mossbauer spectroscopy results, which indicate that the cores are composed of β-FeOOH with two non-equivalent Fe 3+ sites.