Promethium(III) hydroxide

Promethium(III) hydroxide is an inorganic compound with a chemical formula Pm(OH)₃. It is a radioactive compound.

Promethium(III) hydroxide

Identifiers
CAS Number	13779-13-0 Y
3D model (JSmol)	Interactive image
InChI InChI=1S/3H2O.Pm/h3*1H2;/q;;;+3/p-3 Key: HXMRPTXJQXYIQY-UHFFFAOYSA-K
SMILES [Pm+3].[OH-].[OH-].[OH-]
Properties
Chemical formula	Pm(OH)3
Appearance	purplish-pink solid
Density	5.1 g/cm3
Structure
Crystal structure	hexagonal
Lattice constant	a = 6.39 Å, c = 3.68 Å
Related compounds
Other anions	promethium oxide
Other cations	neodymium(III) hydroxide samarium(III) hydroxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

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:^[1]

Pm³⁺ + 3OH⁻ → Pm(OH)₃↓