Structure and properties of 4-phenyl-5H-1,2,3-dithiazole-5-thione polyiodide with S−I+−S bridged complex

Treatment of 4-phenyl-5H-1,2,3-dithiazole-5-thione with iodine in acetonitrile yielded crystalline product with thione-iodonium three-center halogen bond and triiodide anion bound with two iodine molecules by the typical halogen bonds. At the level of a theoretical study of electron density and its gradients, the similarity of electronic properties of the central iodine atom in bridged moiety [S−I−S]+ and in triiodide anion [I−I−I]− has been illustrated. The experimental and theoretical Raman spectra of iodonium salt are discussed: the assignment of the bands corresponding to the iodonium bridged fragment vibrations has been made on the basis of calculated ab initio data.