Organothiometallic compounds. Crystal structure and spectroscopic properties of (isopropylthio)mercury(II) chloride

Abstract

The structure of the title compound was solved from diffractometer data by the heavy-atom method and refined by least-squares techniques to R= 0.056 for 585 observed reflections. Crystals are monoclinic, space group C2, with unit-cell dimensions a= 21.424(6), b= 4.668(2), c= 6.734(3)Å, β= 90.45(5)°, and Z= 2. For each asymmetric unit there are two crystallographically independent mercury atoms. One of them bonds covalently to two sulphur atoms at 2.378 Å, and four chlorine atoms with long contacts (2.985 and 3.342 Å). The co-ordination around the other mercury atom involves two chlorine atoms at 2.534 Å and two sulphur atoms at 2.537 Å. The geometry of the polymeric structure is consistent with i.r. and Raman data. The low values of ν(Hg–S)(231 cm^–1) and ν(Hg–Cl)(218 cm^–1) reflect the interactions of ligand groups in the crystal. Spectroscopic results suggest two types of dissociation pathways on dissolving in pyridine, to form the species Hg(SPrⁱ)Cl, Hg(SPrⁱ)₂, and HgCl₂, and corresponding pyridine adducts.