A new one-dimensional thiocyanato-bridged bimetallic compound [Cu(en)2Mn(NCS)4(H2O)2]n.: Synthesis, crystal structure, and magnetic properties

A bimetallic compound [Cu(en)(2)Mn(NCS)(4)(H2O)(2)](n) (en = ethylenediamine) has been prepared and its structure determined. It crystallizes in space group P (1) over bar, with a = 7.432(1), 6 = 7.492(1), c = 9.751(2) Angstrom, alpha = 91.00(3)degrees, beta = 99.14(3)degrees, gamma = 112.51(3)degrees and Z = 1. The structure consists of one-dimensional chains in which alternating Mn(II) and Cu(II) ions are bridged by NCS ligands. The coordination environment is octahedral for Mn(II) and elongated octahedral for Cu(II). From magnetic susceptibility measurements the compound was found to exhibit a ground state of low-spin multiplicity. Comparison between theory and experimental has been made using I-D model and taking into account the zero-field splitting effect. The decrease in chi(m)T observed at low temperature for the compound is attributed to a dominant zero-field splitting of the single Mn(II) ions with a weak antiferromagnetic interaction superimposed between the Mn(Il) ions via the NCS-Cw-SCN pathway within each chain.