Nonstoichiometric cerium oxides

Sadi et al. [29] suggested that the reactions can be explained by the formation of Ce02- species and oxygen vacancies in the ceria network. Feio et al. [30] showed the formation of nonstoichiometric cerium oxides (Ce02- ) at approximately 633 K. 

Because the tripositive ions are the most stable for all the rare earth elements in almost all compounds, the thermochemistry of the solid (crystalline) rare earth sesquioxides dominates this chapter. Some rare earths have divalent or tetravalent states, so the chemistry of solid monoxides and dioxides are included. There are also many nonstoichiometric binary oxides of cerium, praseodymium, and terbium. As much as possible, the thermochemistry of these nonstoichiometric binary oxides is included. The stability, phase diagrams, and structures of ternary and polynary... 

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