Promethium(III) nitrate
Promethium(III) nitrate is an inorganic compound, a salt of promethium and nitric acid with the chemical formula Pm(NO3)3. The compound is radioactive, soluble in water and forms crystalline hydrates. Synthesis
Reaction of promethium and nitric acid:
Pm + 6HNO3 ->  Pm(NO3)3 + 3NO2 + 3H2O

Physical properties
Promethium(III) nitrate hydrate forms purple-pink solid. Forms crystalline hydrates of the composition Pm(NO3)3*6H2O. Chemical properties
Promethium(III) nitrate thermally decomposes to form Promethium(III) oxide. References

Promethium compounds
Nitrates