Crystal Structure and Magnetic Properties of a Two-dimensional Compound{(Me2NH2)4[Co(SIP)2]·2(DMF)·3(H2O)}n

A new cobalt(II) compound, {(Me2NH2)4[Co(SIP)2]·2(DMF)·3(H2O)}n(1, H3 SIP =5-sulfoisophthalic acid), has been synthesized under solvothermal condition and structurally characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the tetragonal system,space group P 4 21 m, with a = 14.3080(7), b = 14.3080(7), c = 12.1837(9) ?, V = 2494.2(3) ?~3, Z =2, CHNOSCo, Mr = 929.87, Dc = 1.238 g/cm, μ = 0.496 mm, F(000) = 982, flack parameter of 0.007(9), the final R = 0.0767 and wR = 0.2110 for 2391 observed reflections with I >2σ(I). The tetrahedral Co(II) ions are linked by carboxylate groups of the 5-sulfoisophthalate ligands to form an anionic two-dimensional(2D) layer displaying a(4,4) square network, which was charge-balanced by the [MeNH] + cations occupying the spaces between the 2D layers. Magnetic properties of 1 have been investigated in detail using direct-current and alternating-current susceptibility measurements.