Pei‐Pei Yang

Syntheses, crystal structures, and magnetic properties of a series of Fe2Ln complexes

A family of phenoxo-bridged heterometallic Schiff base trinuclear complexes, [Fe2LnL2(C3H7COO)(H2O)]·CH3OH·CH3CN·H2O (Ln = Sm, 1; Gd, 2; Tb, 3; Dy, 4) is reported. Those complexes were afforded by “one-pot” reaction of a polydentate Schiff base ligand 2-hydroxy-3-methoxy-phenylsalicylaldimine (H2L) with Fe(NO3)3·9H2O, Ln(NO3)3·6H2O and sodium butyrate (C3H7COONa) in a mixture of methanol and acetonitrile in the presence of triethylamine as a base. Single-crystal X-ray diffraction analysis reveals that the structures of the four complexes are isomorphic. In each complex, two anionic [FeL2]− units coordinate to the central lanthanide ion as a tetradentate ligand using its four phenoxo oxygens, forming a two-blade propeller-like molecular shape. Magnetic properties of 1–4 were investigated using variable temperature magnetic susceptibility, and weak ferromagnetic exchange between the FeIII and LnIII ions has been established for the Gd derivative. The Tb and Dy complexes show no evidence of slow relaxation behavior above 2.0 K. Graphical abstract The syntheses, crystal structures, and magnetic properties of four heterometallic Schiff base trinuclear [Fe2Ln] complexes are reported. Single-X-ray diffraction analysis reveals that the four complexes contain a blade, propeller-like configuration. Magnetic analysis of GdIII complex shows that the magnetic interaction between GdIII and FeIII ions is weak ferromagnetic.