Plutonium(III) oxide

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]

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

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 I a3.^[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