Skip to Main content Skip to Navigation
Journal articles

Modeling the high-temperature phase coexistence region of mixed transition metal oxides from ab initio calculations

Abstract : Accurate knowledge of phase coexistence regions, i.e., solubility gaps (SGs), is key to the development of mixed transition metal oxides for various applications, such as thermochemical energy storage, or catalysis. However, predicting a SG from first principles in these materials is particularly challenging due to the complex interplay between several sources of entropy, the large configuration space, and the computational expense of ab initio calculations. We present an approach that yields an accurate prediction of the experimental Hausmannite-spinel SG in the case of (CoxMn1-x)3O4. The method uses machine learning to extend an ab initio dataset of hundreds of structures, and it includes many different entropic contributions to the free energy. We demonstrate and quantify the crucial roles of phonon and paramagnetic entropy, and the importance of sampling higher-energy configurations, and correcting for finite-size limitations in the ab initio supercell configurations.
Document type :
Journal articles
Complete list of metadata

https://hal-cea.archives-ouvertes.fr/cea-03642412
Contributor : Contributeur MAP CEA Connect in order to contact the contributor
Submitted on : Friday, April 15, 2022 - 9:30:14 AM
Last modification on : Saturday, April 16, 2022 - 3:39:11 AM

Links full text

Identifiers

Collections

Citation

Suzanne K. Wallace, Ambroise van Roekeghem, Anton S. Bochkarev, Javier Carrasco, Alexander Shapeev, et al.. Modeling the high-temperature phase coexistence region of mixed transition metal oxides from ab initio calculations. Physical Review Research, American Physical Society, 2021, 3, pp.013139. ⟨10.1103/PhysRevResearch.3.013139⟩. ⟨cea-03642412⟩

Share

Metrics

Record views

13