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Updated: May 7, 2026

Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells
Published on: December 13, 2016
Structure and magnetic properties of a new iron(II) citrate coordination polymer
Tadeja Birsa Čelič1, Zvonko Jagličič, Karoly Lazar
1Laboratory for Inorganic Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, Ljubljana 1001, Slovenia.
Abstract:
The new compound [Fe(H2cit)(H2O)]n (NICS-2) is the first neutral ferrous citrate carboxylate that has been synthesized up to now. The iron citrate coordination polymer was hydrothermally synthesized and the structure was solved using single-crystal X-ray diffraction. It crystallizes in an orthorhombic space group P2(1)2(1)2(1) (No. 19), with a = 5.9470 (4), b = 10.402(1) (5), c = 13.5773 (7) Å, V = 839.91 (8) Å(3), Z = 4. Its structure consists of one-dimensional chains of corner-sharing Fe(II)O6 octahedra that are additionally cross-linked with citrate ligands. Chains are additionally stabilized into a pseudo-three-dimensional structure by hydrogen bonds. The measurement of magnetic properties revealed that the magnetic moment is almost constant above 100 K (μeff = 5.1 µB), but decreases rapidly below this temperature most probably due to the appearance of weak antiferromagnetic interactions between Fe atoms. Additionally, analysis of Mossbauer spectra confirmed the presence of divalent Fe atoms in the structure. Thermogravimetrical and X-ray high-temperature diffraction analyses showed the thermal stability of the material up to 548 K.
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