Synthesis, Crystal Structure and Magnetic Property of a One-Dimensional Samarium(III) Coordination Polymer

A novel samarium(III) polymer, [Sm2(C6H5COO)6(CH3OH)3]·CH3OH (1) has been synthesized and characterized by single crystal X-ray diffraction and magnetic measurements. Polymer 1 crystallizes in monoclinic space group P2(1)/c, with a = 15.1247(6), b = 18.3351(7), c = 21.1266(6) A, β = 126.830(2)°, V = 4689.4(3) A3, and Z = 4. Single crystal X-ray analysis reveals a chain-like structure of 1 consisted of alternating eight- and nine-coordinate Sm(III) ions bridged by benzoate ligands in different coordination modes. A treatment of the variable-temperature magnetic susceptibility using an expression deduced from free-ion approximation and molecular field theory suggests the existence of a weak antiferromagnetic coupling between the samarium ions. A novel one-dimensional samarium polymer containing alternating eight- and nine-coordinate Sm(III) ions has been generated by incorporating benzoic acid in three different binding modes in its deprotonated state.