Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
Promethium(III) hydroxide is an inorganic compound with a chemical formula Pm(OH)3. It is a radioactive compound.
Production
Promethium(III) hydroxide can be produced by reacting ammonia water with a solution of a promethium(III) salt, from which promethium(III) hydroxide precipitates as a purplish-pink amorphous solid. By heating with water, it can be forced to crystallize, giving hexagonal crystals isomorphous with other rare earth hydroxides:
Pm + 3OH → Pm(OH)3↓
References
Weigel, Fritz; Scherer, Volker (1967). "Die Chemie Des Promethiums. VI. Kristallines Promethium(III)-hydroxid" [Chemistry of promethium. VI. Crystalline promethium(III) hydroxide]. Radiochimica Acta (in German). 7 (2–3): 72–74. doi:10.1524/ract.1967.7.23.72. S2CID201841420.