PuO22

PuO22 is not a recognized chemical compound in the plutonium-oxygen system. As a neutral, discrete oxide, there is no known stable compound with the formula PuO22 that satisfies plausible chemical oxidation states; a composition implying twenty-two oxygens per plutonium would require an unrealizable oxidation state for plutonium. Consequently, PuO22 does not appear in standard chemical databases or phase diagrams and is generally regarded as a misnotation or typographical error rather than a distinct species.

In contrast, well-established plutonium oxides include PuO2 (plutonium dioxide), Pu2O3 (plutonium(III) oxide), and PuO3 (plutonium(VI) oxide). PuO2 is the most common and stable oxide under many conditions and forms a fluorite-type lattice. Pu2O3 and PuO3 can be produced under specific redox environments or high-temperature treatments. Under oxidizing conditions, nonstoichiometric oxides such as PuO2+x can occur, reflecting oxygen interstitials in the crystal lattice and resulting in compositions slightly richer in oxygen than PuO2.

PuO2-based materials are important in the nuclear fuel cycle, as well as in spent fuel management and long-term waste immobilization. They are highly radiotoxic and primarily alpha emitters, requiring stringent handling, containment, and regulatory controls. The chemistry of plutonium oxides influences oxygen diffusion, redox behavior, and material stability under irradiation.

If PuO22 is encountered in a text, it is typically a typographical error or a misreading of PuO2, a notation for a nonstoichiometric oxide, or a hydration-related form rather than a distinct chemical compound. See also plutonium dioxide, plutonium oxide, and nonstoichiometric oxides.