About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Thermodynamics of Ferroelectrics beyond Phenomenological Landau Theory: A Case Study of PbTiO3 |
Author(s) |
Zi-Kui Liu, Jinglian Du, Yi Wang, Shunli Shang |
On-Site Speaker (Planned) |
Zi-Kui Liu |
Abstract Scope |
Thermodynamics of ferroelectric materials with characteristic ferroelectric to paraelectric (FE-PE) transitions has been described by the phenomenological Landau theory. Here we present a multiscale entropy approach that can predict the FE-PE transition from first-principles calculations based on density functional theory (DFT) without fitting parameters. The present approach considers the entropic contributions from the ferroelectric domain configurations in addition to electronic and quasiharmonic phonon contributions. With inputs exclusively from DFT-based first-principles calculations, the FE-PE transition temperature in PbTiO3 is predicted showing remarkable agreement with experimental observations. The present approach is supported by the observations that the macroscopically cubic paraelectric phase is microscopically tetragonal with polarization by x-ray absorption fine-structure structure technique and ab initio molecular dynamic simulations. |
Proceedings Inclusion? |
Planned: |