Bismuth(III) iodide adopts a distinctive crystal structure, with iodide centres occupying a hexagonally closest-packed lattice, and bismuth centres occupying either none or two-thirds of the octahedral holes (alternating by layer), therefore it is said to occupy one third of the total octahedral holes.[5][6]
Synthesis
Bismuth(III) iodide forms upon heating an intimate mixture of iodine and bismuth powder:[7][8]
Since bismuth(III) iodide is insoluble in water, an aqueous solution can be tested for the presence of Bi3+ ions by adding a source of iodide such as potassium iodide. A black precipitate of bismuth(III) iodide indicates a positive test.[10]
Bismuth(III) iodide forms iodobismuth(III) anions when heated with halide donors:[11]
Bismuth(III) iodide catalyzes the Mukaiyama aldol reaction. Bi(III) is also used in a Barbier type allylation of carbonyl compounds in combination with a reducing agent such as zinc or magnesium.
References
^John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 5–188. ISBN978-1138561632.
^
Turner, Jr., Francis M.; Berolzheimer, Daniel D.; Cutter, William P.; Helfrich, John (1920), The Condensed Chemical Dictionary, New York: Chemical Catalog Company, p. 107, retrieved 2008-06-19