Plutonium(III) oxide

Plutonium(III) oxide

Names
Other names Diplutonium trioxide
Identifiers
CAS Number	12036-34-9  N [1]
3D model (JSmol)	Interactive image
InChI InChI=1S/3O.2Pu/q3*-2;2*+3 Key: KNXZYWXJSDQACR-UHFFFAOYSA-N
SMILES [O-2].[O-2].[O-2].[Pu+3].[Pu+3]
Properties
Chemical formula	Pu2O3
Molar mass	536 g·mol−1
Density	11 g/cm3
Melting point	2,085 °C (3,785 °F; 2,358 K)
Related compounds
Other anions	Triuranium octoxide Diuranium pentoxide Uranium trioxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Plutonium(III) oxide is an inorganic compound of plutonium and oxygen with the chemical formula Pu₂O₃. This is a sesquioxide of plutonium and is a lower oxide compared to the more common plutonium dioxide PuO₂. ^[2]

Synthesis

The cubic modification of the compound is formed by thermal dissociation of plutonium dioxide: ^[3]

2PuO₂ → Pu₂O₃ + O₂

The hexagonal modification is formed during the reduction of plutonium dioxide with metallic plutonium:

2PuO₂ + Pu → 2Pu₂O₃

Physical properties

The compound forms black crystals of cubic system, space group Ia3. ^{[4] [5]}

The compound also forms crystals of hexagohal system, space group P 3m1. ^[6]

Сhemical properties

The compound oxidizes when stored in open air: ^[6]

2Pu₂O₃ + O₂ → 4PuO₂

References

1. "WebElements Periodic Table » Plutonium » diplutonium trioxide". webelements.com. Retrieved 26 November 2025.
2. Los Alamos Science. The Laboratory. 2000. p. 258. Retrieved 26 November 2025.
3. Guéneau, Christine; Chatillon, Christian; Sundman, Bo (September 2008). "Thermodynamic modelling of the plutonium–oxygen system". Journal of Nuclear Materials . 378 (3): 257–272. doi:10.1016/j.jnucmat.2008.06.013.
4. "Pu2O3, ID: mp-637224". Materials Project . Retrieved 26 November 2025.
5. Volʹskiĭ, Anton Nikolaevich; Sterlin, I︠A︡kov Moiseevich (1970). The Metallurgy of Plutonium. Israel Program for Scientific Translations; [available from the U.S. Department of Commerce, Clearinghouse for Federal Scientific and Technical Information, Springfield, Va.] p. 48. Retrieved 26 November 2025.
6. Yang, Yu; Lu, Yong; Zhang, Ping (1 September 2014). "Optical properties of PuO2 and α-Pu2O3". Journal of Nuclear Materials. 452 (1): 414–418. doi:10.1016/j.jnucmat.2014.05.070. ISSN   0022-3115 . Retrieved 26 November 2025.