In the mol­ecule of the title compound, [InCl3(C12H12N2)(C2H6OS)], the InIII atom is six-coordinated in a distorted octa­hedral configuration by two N atoms from the chelating 4,4′-dimethyl-2,2′-bipyridine ligand, one O atom from dimethyl sulfoxide and three Cl atoms. In the crystal structure, inter­molecular C—H⋯Cl hydrogen bonds link the mol­ecules into centrosymmetric dimers.

Key indicators: single-crystal X-ray study; T = 298 K; mean (C-C) = 0.008 Å; R factor = 0.043; wR factor = 0.127; data-to-parameter ratio = 25.3.The complete molecule of the title compound, [ZnI 2 (C 12 H 12 N 2 )], is generated by crystallograpic twofold symmetry, with the Zn II atom lying on the rotation axis. The Zn II atom is coordinated by the N,N-bidentate 6,6 0 -dimethyl-2,2 0 -bipyridine ligand and two iodide ions, resulting in a distorted ZnN 2 I 2 tetrahedral geometry for the metal. In the crystal, there are weak -contacts between the pyridine rings [centroid-centroid distance = 3.978 (3) Å ]. Related literature

The asymmetric unit of the title compound, [CdCl2(C12H12N2)]n, contains one half-mol­ecule; a twofold rotation axis passes through the Cd atom. The CdII atom is six-coordinated in a distorted octa­hedral configuration by two N atoms from 2,2′-bipyridine-5,5′-dimethyl and four bridging Cl atoms. The bridging function of the chloro atoms leads to a one-dimensional chain structure. There is a π–π contact between the pyridine rings [centroid–centroid distance = 3.9807 (9) Å].

In the mol­ecule of the title compound, [ZnCl2(C11H10N2)], the ZnII atom is four-coordinated in a distorted tetra­hedral configuration by two N atoms from the 6-methyl-2,2′-bipyridine ligand and by two Cl atoms. There are π–π contacts between the pyridine ring and the five-membered ring, and also between the pyridine rings, [centroid–centroid distances = 3.685 (3) and 3.757 (3) Å, respectively].

Key indicators: single-crystal X-ray study; T = 298 K; mean (C-C) = 0.007 Å; R factor = 0.037; wR factor = 0.098; data-to-parameter ratio = 25.1.In the title coordination polymer, [CdI 2 (C 12 H 12 N 2 )] n , the Cd 2+ ion lies on a twofold rotation axis: it is six-coordinated in a distorted cis-CdN 2 I 4 octahedral geometry by two N atoms from a chelating 5,5 0 -dimethyl-2,2 0 -bipyridine ligands and four bridging iodide anions. The bridging function of the iodide ions leads to a chain structure propagating in [001]. Related literature