Holmium(III) iodide hydrate can be converted to the anhydrous form by dehydration with a large excess of ammonium iodide (since the compound is prone to hydrolysis).[4]
Properties
Holmium(III) iodide is a highly hygroscopic substance that dissolves in water.[7][3][2] It forms yellow hexagonal crystals with a crystal structure similar to bismuth(III) iodide.[4] In air, it quickly absorbs moisture and forms hydrates. The corresponding oxide iodide is also readily formed at elevated temperature.[4]
References
^Jantsch, G.; Jawurek, H.; Skalla, N.; Gawalowski, H. (1932). "Zur Kenntnis der Halogenide der seltenen Erden. VI. Über die Halogenide der Terbin- und Erbinerdengruppe" [Halides of the rare earths. VI. Halides of the terbium and erbium earth groups]. Zeitschrift für Anorganische und Allgemeine Chemie (in German). 207 (4): 353–367. doi:10.1002/zaac.19322070404.
^ abcdeGeorg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: Handbuch der Präparativen Anorganischen Chemie. 3., umgearbeitete Auflage. Band I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6, S. 1077.