Thermodynamic properties of nonstoichiometric oxygen in manganite Ca0.9Pr0.1MnO3–δ
- Authors: Leonidov I.A.1, Konstantinova E.I.1, Patrakeev M.V.1, Kozhevnikov V.L.1
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Affiliations:
- Institute of Solid State Chemistry
- Issue: Vol 90, No 11 (2016)
- Pages: 2123-2128
- Section: Chemical Thermodynamics and Thermochemistry
- URL: https://journals.rcsi.science/0036-0244/article/view/168912
- DOI: https://doi.org/10.1134/S0036024416110133
- ID: 168912
Cite item
Abstract
The chemical potential of oxygen ΔμO relative to its standard state in the gas phase was calculated from the experimental dependences of the oxygen content in various polymorphic modifications of Ca0.9Pr0.1MnO3–δ on the partial pressure and temperature. The partial molar enthalpy \(\Delta {\overline H _O}\) and entropy \(\Delta {\overline S _O}\) of oxygen were obtained from the linear temperature dependences of ΔμO. Based on the ideal solution approximation, \(\Delta {\overline H _O}\) and \(\Delta {\overline S _O}\) were correlated with the enthalpies and entropies of the defect formation reactions, the concentrations of manganese cations, and the oxygen nonstoichiometry. The thermal excitation of Mn4+ cations was shown to substantially affect the thermodynamic functions of oxygen.
About the authors
I. A. Leonidov
Institute of Solid State Chemistry
Author for correspondence.
Email: leonidov@imp.uran.ru
Russian Federation, Yekaterinburg
E. I. Konstantinova
Institute of Solid State Chemistry
Email: leonidov@imp.uran.ru
Russian Federation, Yekaterinburg
M. V. Patrakeev
Institute of Solid State Chemistry
Email: leonidov@imp.uran.ru
Russian Federation, Yekaterinburg
V. L. Kozhevnikov
Institute of Solid State Chemistry
Email: leonidov@imp.uran.ru
Russian Federation, Yekaterinburg