text: Lanthanum(III) iodide is very soluble in water and is deliquescent. Anhydrous lanthanum(III) iodide reacts with tetrahydrofuran to form a photoluminescent complex, LaI(THF), with an average La–I bond length of 3.16 Å. This complex is a starting material for amide and cyclopentadienyl complexes of lanthanum.