About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
|
Symposium
|
Advances in Multiphysics Modeling and Multi-modal Imaging of Functional Materials
|
Presentation Title |
Identifying Internal Process Order Parameters in Nonstoichiometric Oxides Described by Sublattice Model |
Author(s) |
Yanzhou Ji, Yueze Tan, Long-Qing Chen |
On-Site Speaker (Planned) |
Yanzhou Ji |
Abstract Scope |
In CALPHAD-type thermodynamic databases, nonstoichiometric oxides are typically described by sublattice models where the sublattice site fractions represent the occupation probability of different atomic, ionic or defect species on different sublattices. It has been shown that the sublattice site fraction can be converted to a combination of independent component compositions and internal process order parameters describing the extent of the internal atomic exchange, electronic redox and defect generation reactions. In this study, we develop the general procedure for this conversion, and apply this tool to general nonstoichiometric phases available in existing thermodynamic databases and literature. We will also show how this tool can facilitate the thermodynamic stability analysis and phase-field modeling of nonstoichiometric oxides. |