Plutonium trihydride

Plutonium trihydride

Names
IUPAC name Plutonium trihydride
Other names Plutonium(III) hydride
Identifiers
CAS Number	15457-77-9  N
3D model (JSmol)	Interactive image
InChI InChI=1S/Pu.3H2/h;3*1H Key: FYCLQSJNZIPDAJ-UHFFFAOYSA-N
SMILES [HH].[HH].[HH].[Pu]
Properties
Chemical formula	PuH3
Molar mass	247 g·mol−1
Appearance	grey crystals
Density	9610 kg/m3
Melting point	327 °C (621 °F; 600 K)
Solubility in water	soluble
Related compounds
Other cations	Americium trihydride Uranium trihydride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Plutonium trihydride is an compound of plutonium and hydrogen with the chemical formula PuH₃. ^{[1] [2] [3]}

Synthesis

Plutonium reacts noticeably with hydrogen at room temperature and rapidly when heated: ^[4]

2Pu + 3H₂ → 2PuH₃

Also, heating of plutonium dihydride with hydrogen:

2PuH₂ + H₂ → 2PuH₃

Physical properties

Plutonium trihydride forms grey crystals of hexagonal crystal structure ^{[5] [6]} , space group P63/mmc.

The compound is very toxic by radiotoxicity and spontaneously flammable in air. It ignites on contact with water. Contamination dangerous due to radiation and toxic hazards. When heated to decomposition it emits extremely toxic and radioactive fumes of Pu. ^[7]

Chemical properties

When heated in an ammonia atmosphere, it forms a plutonium nitride: ^[8]

PuH₃ + NH₃ → PuN + 3H₂

It reacts with air: ^[9]

PuH₃ + O₂ + N₂ → Pu₂O₃ + PuN + H₂

References

1. "WebElements Periodic Table » Plutonium » plutonium trihydride". winter.group.shef.ac.uk. Retrieved 5 October 2025.
2. Balasubramanian, K.; Felter, Thomas E.; Anklam, Thomas; Trelenberg, Thomas W.; McLean, William (11 October 2007). "Atomistic level relativistic quantum modelling of plutonium hydrogen reaction". Journal of Alloys and Compounds . pp. 447–452. doi:10.1016/j.jallcom.2006.11.068 . Retrieved 5 October 2025.
3. Bailar, J. C. (15 October 2013). Comprehensive Inorganic Chemistry. Elsevier. p. 141. ISBN   978-1-4832-8313-5 . Retrieved 5 October 2025.
4. Peterson, Sigfred (1955). Fundamental Chemistry for Nuclear Reactor Engineers. U. S. Atomic Energy Commission. p. 80. Retrieved 5 October 2025.
5. Donnay, Joseph Désiré Hubert (1963). Crystal Data; Determinative Tables. American Crystallographic Association. p. 766. Retrieved 5 October 2025.
6. Donnay, Joseph Désiré Hubert (1973). Crystal Data: Inorganic compounds. National Bureau of Standards. p. 221. Retrieved 5 October 2025.
7. "Plutonium hydride (PuH3)". guidechem.com. Retrieved 5 October 2025.
8. Ahrland, S.; Bagnall, K. W.; Brown, D. (7 June 2016). The Chemistry of the Actinides: Comprehensive Inorganic Chemistry. Elsevier. p. 150. ISBN   978-1-4831-5934-8 . Retrieved 5 October 2025.
9. Haschke, John M.; Dinh, Long N. (25 March 2017). "Chemistry and kinetics of the pyrophoric plutonium hydride-air reaction". Journal of Alloys and Compounds . 698: 44–48. doi:10.1016/j.jallcom.2016.12.162. ISSN   0925-8388 . Retrieved 5 October 2025.