Cadmium iodide complexes with dimethylsulphoxide, and their crystal structures

The crystalline compounds [{CdI 2 (dmso)} n ] ( 1 ,) and [Cd 2 I 4 (dmso) 4 ] ( 2 ,) provide a structural sequence illustrating the conversion of CdI 2 into the ionic derivatives [Cd(dmso) 6 ] 2+ [Cd(dmso)I 3 ] 2 − · EtOH ( 3 ,) and [Cd(dmso) 6 ] 2+ CdI 4 2− ( 4 ,), with increasing proportions of dmso. ( 1 ,) comprises polymeric chains with Cd centres linked by bridging iodide atoms, and alternately in four‐ and six‐coordination. ( 2 ,) is a binuclear segment of the chains and can be seen as the structural forerunner of the ionic compounds ( 3 ,) and ( 4 ,). The ion packing in ( 3 ,) is loose, with lattice ethanol.