Two-dimensional carboxylate bridged network of europium(III)-transition metal(II) glutarate compounds

Four new heterometallic glutarate coordination polymers, [Eu2M(H2O)(4)][O2C(CH2)(3)CO2](4)center dot 2H(2)O (M=Mn (1), Fe (2), Co (3) and Ni (4)) have been obtained under hydrothermal synthesis. The single-crystal X-ray diffraction analyses showed that they have two-dimensional frameworks based on the linear polyhedral chains consisting of two nine-coordinated Eu(III)O-9 and a six-coordinated M(II)O-6. These 1-D MO6-Eu2O16 chains are cross-linked by glutarate ligands as an interchain pillared architecture, whose conformations vary depending upon the transition metals. The magnetic behavior of the compounds show a weak antiferromagnetic interaction, in which shielding of the 4f electrons by the outer shell electrons effectively precludes significant coupling interactions between the Eu-4f electrons and transition metal (M)-3d electrons.