Cerium(III) iodide

Cerium(III) iodide (CeI3) is the compound formed by cerium(III) cations and iodide anions.

Preparation
Cerium metal reacts with iodine when heated to form cerium(III) iodide:


 * 2 Ce + 3 I2 -> 2 CeI3

It is also formed when cerium reacts with mercury(II) iodide at high temperatures:


 * 2 Ce + 3 HgI2 -> 2 CeI3 + 3 Hg

Structure
Cerium(III) iodide adopts the plutonium(III) bromide crystal structure. It contains 8-coordinate bicapped trigonal prismatic Ce3+ ions.

Uses
Cerium(III) iodide is used as a pharmaceutical intermediate and as a starting material for organocerium compounds.