Crystal and molecular structure of mercury(II) tetrathiocyanatobis(dimethylformamide)cobaltate(II)

Abstract

The crystal and molecular structure of mercury(II) tetrathiocyanatobis(dimethylformamide)cobaltate(II) Hg(SCN) 4Co(DMF) 2 was determined from three-dimensional X-ray data collected by counter methods. The pink prismatic crystals are monoclinic, space group P2 1/n. The unit cell dimensions are a = 9.163(2), b = 14.057(3), c = 16.276(3) Å, β = 92.88(3)° and Z = 4. The structure was solved by direct methods from 3298 reflections and refined by least-squares methods to R = 0.053. The structure is polymeric with the four sulphur atoms of the thiocyanate groups tetrahedrally coordinated around the mercury atom. The average HgS bond length is 2.525 Å. The linear thiocyanate groups have a mean angle of 96.5° to the HgS bonds. The dimethylformamide molecules are bonded to the cobalt atom in cis configuration through the oxygen atoms with average CoO distance of 2.114 Å and an OCoO angle of 88.2°. Octahedral six-coordination around cobalt is completed by the thiocyanate N atoms of four Hg(SCN) 4 units with mean CoN bond lengths of 2.113 Å.