Structural diversity in Cd(NCS)2-3-cyanopyridine coordination compounds: synthesis, crystal structures and thermal properties

Abstract

Abstract Five new compounds with the compositions [Cd(NCS)2(3-cyanopyridine)2] n  · 3-cyanopyridine (1), [Cd(NCS)2(3-cyanopyridine)2] n  · 1/3 3-cyanopyridine (2), [Cd(NCS)2(3-cyanopyridine)2] n (3), {[Cd(NCS)2]2(3-cyanopyridine)3} n (4), and {[Cd(NCS)2]3(3-cyanopyridine)4} n (5) have been obtained by the reaction of Cd(NCS)2 with 3-cyanopyridine in different solvents. While large amounts of compounds 1–4 could be prepared as powders, only a few single crystals of 5 were accidently obtained. Thermoanalytical investigations have shown that 4 could also be obtained by annealing of 1 or 2 and that under slightly different conditions 5 could be obtained as part of a mixture with 4. The crystal structures of all compounds can be divided in two sets of compounds. Compounds 1, 2 and 3 consist of chains in which the Cd cations show three different coordination environments and in which the coligands are only terminally bonded. In the structures of 4 and 5 similar chains are observed, which are connected into layers via some of the 3-cyanopyridine coligands.