Iridium(III) iodide is an

iodide An iodide ion is the ion I−. Compounds with iodine in formal oxidation state −1 are called iodides. In everyday life, iodide is most commonly encountered as a component of iodized salt, which many governments mandate. Worldwide, iodine def ...

iridium Iridium is a chemical element with the symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal (after osmium) with a density of ...

, with the chemical formula of IrI₃.

Preparation

Iridium(III) iodide can be obtained by reducing iridium(IV) iodide with hydrogen at 210 °C. It can also be formed by the reaction of

iridium dioxide Iridium(IV) oxide, IrO2, is the only well-characterised oxide of iridium. It is a blue-black solid. The compound adopts the TiO2 rutile structure, featuring six coordinate iridium and three coordinate oxygen. It is used with other rare oxides in t ...

or iridium(III) hydroxide with

hydrogen iodide Hydrogen iodide () is a diatomic molecule and hydrogen halide. Aqueous solutions of HI are known as hydroiodic acid or hydriodic acid, a strong acid. Hydrogen iodide and hydroiodic acid are, however, different in that the former is a gas under s ...

Chemical properties

Iridium(III) iodide is a dark brown solid that is insoluble in water. It is

monoclinic In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic ...

chromium trichloride Chromium(III) chloride (also called chromic chloride) describes any of several chemical compounds with the formula CrCl3, where can be 0, 5, and 6. The anhydrous compound with the formula CrCl3 is a violet solid. The most common form of the tri ...

. Its trihydrate is yellow and can be dehydrated into the dihydrate or anhydrous form on heating. Iridium(III) iodide also has a monohydrate.

References

{{Iodides Iridium compounds Iodides Platinum group halides