Syntheses, structures and magnetic properties of isonicotinate-bridged heterometallic Ln(III)-Cu(II) coordination polymers

The heterometallic Ln(III)-Cu(II) coordination polymers [CuLn2(IN)8(H2O)4]n (IN = isonicotinate, Ln = Gd (1), Dy (2), Er(3)) have been synthesized by hydrothermal reactions and characterized by elemental analysis, IR and single crystal X-ray diffraction. The compounds are isomorphous and crystallize in monoclinic space group P21/c, adopting a one-dimensional chain structure with alternately arranged [Ln2(IN)6(H2O)4] and [Cu(IN)2] building blocks bridged by isonicotinates. Temperature-dependent magnetic susceptibility for complex 1 was studied, and a very weak ferromagnetic interaction between metal ions was observed.