Europium(III) iodide

Europium iodide is an inorganic compound, a salt containing europium and iodine with the chemical formula.

Preparation

Europium metal reacts directly with iodine to form europium iodide:
Hydrated europium iodide can be prepared dissolving europium(III) oxide or europium(III) carbonate in hydroiodic acid:
Europium powder reacts with iodine in THF to form a THF adduct of europium iodide:
The adduct can be formulated more simply as.

Structure

Europium iodide adopts the bismuth(III) iodide crystal structure type, with octahedral coordination of each Eu³⁺ ion by 6 iodide ions.

Reactivity

Europium iodide is used as the starting material for two of the main ways of preparing europium(II) iodide:
Reduction with hydrogen gas at 350 °C:
Thermal decomposition at 200 °C, a disproportionation reaction:
Europium iodide nonahydrate, EuI₃·9H₂O, thermally decomposes to europium iodide dihydrate, EuI₂·H₂O.