Inorganic Iodides

Iodine forms iodide compounds with almost all of the elements except inert elements, as shown in this chapter. Commercially available inorganic iodides are the most important class of iodine compounds. Some of the inorganic iodides discussed in the chapter are hydrogen iodide, hydriodic acid, sodium iodide, potassium iodide, copper (I) iodide, silver iodide, nitrogen iodide and iodine pentoxide. Iodine also reacts with other halogens, fluorine, chlorine, and bromine, and forms interhalogens. The chapter summarizes physicochemical properties and preparation methods of some representative inorganic iodides and iodo compounds. A special case of interhalogen compounds are those containing iodine only: so-called polyiodides. The triiodide ion can be regarded as the most simple polyiodide ion. The bonding in polyiodides is complex involving contributions from long-range covalent interaction, as well as induction, ion-quadrupole, and dispersion interactions.