Structural versatility driven by the flexible di(4-pyridyl) sulfide ligand: From cobalt(II) single-ion magnets to sheet-like copper(II) weak antiferromagnets

The reaction between the ligand di(4-pyridyl)sulfide (dps) and two salts of divalent first row transition metals (M = Co2+, and Cu2+) resulted in three new compounds with formula: [Co(dps)4(H2O)2](ClO4)2⋅H2O (1), [Cu(dps)2(dmso)2]n(ClO4)2n (2) and [{Cu(dps)2(dmso)2}{Cu(dps)2(dmso)(H2O)}]n(ClO4)4n⋅2nH2O⋅n(dmso) (3). Crystal structures of 1–3 were determined using single-crystal X-ray diffraction. Crystal structure of 1 consists of a mononuclear complex, in which the dps ligand acts in a monodentate mode through one of the pyridyl nitrogen atoms. Compounds 2 and 3 present the dps ligands bridging metal centers leading to bidimensional coordination polymers. Magnetic properties in the polycrystalline samples of 1–3 in the 300–2 K temperature range were investigated. Complex 1 exhibits a field-induced slow magnetization behavior and behaves as a single-ion magnet with an effective energy barrier for the reversal of magnetization of 22.9 (1.1) K and τ0 = 5.3(1.2) × 10−7 s.