Cerium redox equilibria

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Edward Grew

Subject: Cerium redox equilibria

Is anybody aware of experimental work on CeO2 - Ce2O3 equilibria? I am looking for a T - f(O2) diagram for Ce oxides.

From: J. Michael Palin

Subject: Re: Cerium redox equilibria

I seem to remember various multiple valence oxide pairs, including

CeO4-Ce2O3 and Eu2O3-EuO, shown on a T-fO2 diagram in: Carmichael, I.S.E. & Ghiorso, M.S. (1990): The effect of oxygen fugacity on the redox state of natural liquids and their crystallizing phases. in ¨Modern methods of igneous petrology: Understanding magmatic processes¨, J. Nicholls & J.K. Russell, eds., Mineralogical Society of America, Reviews in Mineralogy, 24, 191-212. There may also be something particular to Ce in: H.D. Schreiber, H.V. Luer, T. Thanyasiri (1980) The redox state of cerium in basaltic magmas: an experimental study of iron-cerium interactions in silicate melts, Geochim. Cosmochim. Acta 44: 1599-1612.

From: Kees Linthout

Subject: Re: cerium redox equilibria

For a logfO2 vs. T diagram of the CeO2/Ce2O3 equilibrium and its calculation from the delta G data, see Appendix 1 in Hanchar et al. (2001, Am. Min. 86, 667-680).

From: Eric Essene

Subject: Re: Cerium redox equilibria

You don't need experiments, just the delta G data for Ce2O3 and CeO2. That is only a crude guide however for the oxidation state of Ce in silicate crystals or liquids, unfortunately.