Solvothermal synthesis, crystal structure and magnetic properties of homometallic Co(II) and Cu(II) chains with double di(4-pyridyl)sulfide as bridges

Abstract

Two new coordination polymers {[Co(μ-4,4′-dps)2(H2O)2](NO3)2·2(4,4′-dps)·4H2O}n (1) and {[Cu(μ-4,4′-dps)2(H2O)2](NO3)2·2H2O}n (2) [4,4′-dps=di(4-pyridyl)sulfide] have been synthesized by solvothermal reactions between the nitrate salts of cobalt(II) (1) and copper(II) (2) and the 4,4′-dps molecule. Compounds 1 and 2 have been characterized by elemental analysis, thermal analysis (TG/DTA), vibrational spectroscopy, single crystal X-ray diffraction analysis and variable-temperature magnetic measurements. Compounds 1 and 2 are cationic chain compounds of formula {[M(μ-4,4′-dps)2(H2O)2]n2n+ [M=Co(II) (1) and Cu(II) (2)] with double 4,4′-dps bridges, uncoordinated nitrate anions, and crystallization water (1 and 2) and 4,4′-dps (1) molecules. Each metal ion in 1 and 2 is six-coordinated with two coordinated water molecules in trans position and four pyridyl-nitrogen atoms from four 4,4′-dps ligands building a distorted octahedral environment. The values of the intrachain metal–metal separation are 9.940(4) and 9.702(4)Å for 1 and 2, respectively. The magnetic properties of 1 and 2 correspond to those of magnetically isolated copper(II) and high-spin cobalt(II) centers, the extended 4,4′-dps bridge being a poor mediator of magnetic interactions.