Poly[tris-(μ-4,4'-bi-pyridine-κ(2) N:N')bis(dimethyl sulfoxide-κO)tetra-kis-(thiocyanato-κN)dicobalt(II)].

The asymmetric unit of the title compound, [Co2(NCS)4(C10H8N2)3(C2H6OS)2] n , consists of one Co(II) atom, two thio-cyanate anions, one dimethyl sulfoxide mol-ecule and one and a half 4,4'-bi-pyridine mol-ecules. The half-molecule is completed by inversion symmetry. The Co(II) atom is coordin-ated in a distorted octa-hedral geometry by two N atoms from two thio-cyanate anions, one O atom from dimethyl sulfoxide as a terminal ligand and three N atoms from three 4,4'-bi-pyridine mol-ecules as bridging ligands linking the cations, with a Co⋯Co separation of 11.5964 (5) Å. This generates a two-dimensional structure parallel to (-103). A C-H⋯S hydrogen bond links the layers into a three-dimensional supra-molecular framework. The layers are stacked in an ABC fashion preventing the occurrence of inter-layer void space and hence leading to the absence of lattice solvent and/or organic guest mol-ecules in the structure.