Solid solution of transition metal-dicarboxylates with tunable magnetic properties

Single crystals of inorganic–organic hybrid compounds, M5(OH)2[CO2(CH2)2CO2]4 [M = Mn(Mn-s), Fe(Fe-s), Co(Co-s), Mn/Fe(Mn---Fe-n) and Mn/Co(Mn---Co-n)] were prepared under hydrothermal condition at 180 °C from a mixture of transition metal(II) chlorides, succinic acid, potassium hydroxide, and water. Crystal structure of all compounds present the same structural type in the single-crystal X-ray diffraction refinements and X-ray powder diffraction analysis. The single crystal structural analyses for three homo-metallic compounds were performed and the prepared compounds have divalent metal ions on the basis of bond valence sum calculations. The unit cell constants for the hetero-metallic compounds, e.g., Mn/Fe, Mn/Co solid solutions were determined. Magnetic measurements show that the Mn-s may have antiferromagnetic interaction at low temperature. The Fe-s and the Co-s compounds have ferrimagnetic coupling below 10 K. The Mn---Co-n compounds show the ferromagnetic magnetic behavior while the Mn---Fe-n compounds present antiferromagnetic ordering.