Kristallstruktur des Cadmiumthiocyanat-Hexamethylentetramin-Addukts Cd(SCN)2·C6H12N4 · 2H2O/ Crystal Structure of the Cadmium Thiocyanate Hexamethylenetetramine Adduct Cd(SCN )2· C6H12N4 · 2H2O

Abstract

Crystals of the adduct Cd(SCN )2 ·C6H12N4 · 2H2O were obtained by diffusion of an aqueous solution of hexamethylenetetramine into an aqueous solution of cadmium thiocyanate. The crystals are triclinic, space group P 1̄, Z = 2, a = 600.4(2), b = 1005.1(3), c = 1283.9(4) pm , α= 105.79(9), β = 102.63(7), γ = 103.65(3)°. Each cadmium atom is bonded to one hexamethylenetetramine ligand, one water molecule, and, via the N atoms, to two NCS groups, which act as bridging ligands and form bonds, via the S atoms, to adjacent cadmium atoms. Thus a polymeric chain structure is formed. There is an other water molecule present per formula unit, which is not coordinated to cadmium but is located in channels between the chains. Between the oxygen atoms of this water molecule and the oxygen atom of the coordination water molecule, as well as the nitrogen atom of the hexamethylenentetramine ligand, a system of hydrogen bonds is formed. The coordination of the cadmium atoms is approximately octahedral.