English

Thermodynamic modeling with uncertainty quantification using the modified quasichemical model in quadruplet approximation: Implementation into PyCalphad and ESPEI

Computational Physics 2022-05-24 v2

Abstract

The modified quasichemical model in the quadruplet approximation (MQMQA) considers the first- and the second-nearest-neighbor coordination and interactions, particularly useful in describing short-range ordering in complex liquids such as molten salts, slag in metal processing, and electrolytic solutions. The present work implements the MQMQA into the Python based open-source software PyCalphad for thermodynamic calculations. This endeavor facilitates the development of MQMQA-based thermodynamic database with uncertainty quantification (UQ) using the open-source software ESPEI. A new database structure based on Extensible Markup Language (XML) is proposed for ESPEI evaluation of MQMQA model parameters. Using the KF-NiF2 system as an example, we demonstrate the successful implementation of MQMQA in PyCalphad through thermodynamic calculations of Gibbs energy, equilibrium quadruplet fractions, and phase diagram, as well as database development with UQ using ESPEI. The present implementation offers an open-source capability for performing CALPHAD modeling for complex liquids with short-range ordering using MQMQA.

Keywords

Cite

@article{arxiv.2204.09111,
  title  = {Thermodynamic modeling with uncertainty quantification using the modified quasichemical model in quadruplet approximation: Implementation into PyCalphad and ESPEI},
  author = {Jorge Paz Soldan Palma and Rushi Gong and Brandon J. Bocklund and Richard Otis and Max Poschmann and Markus Piro and Yi Wang and Tatiana G. Levitskaia and Shenyang Hu and Hojong Kim and Zi-Kui Liu and Shun-Li Shang},
  journal= {arXiv preprint arXiv:2204.09111},
  year   = {2022}
}

Comments

Note that the Supplemental Materials/files can be found in https://doi.org/10.5281/zenodo.6471272

R2 v1 2026-06-24T10:52:34.810Z