Jump to main content
Jump to site search

Issue 12, 2015
Previous Article Next Article

A molecular dynamics study of oxygen ion diffusion in A-site ordered perovskite PrBaCo2O5.5: data mining the oxygen trajectories

Author affiliations

Abstract

Molecular dynamics (MD) simulations have been widely used to study oxygen ion diffusion in crystals. In the data analysis, one typically calculates the mean squared displacements to obtain the self-diffusion coefficients. Further information extraction for each individual atom poses significant challenges due to the lack of general methods. In this work, oxygen ion diffusion in A-site ordered perovskite PrBaCo2O5.5 is studied using MD simulations and the oxygen migration is analyzed by k-means clustering, a machine learning algorithm. The clustering analysis allows the tracking of each individual oxygen jump along with its corresponding location, i.e., oxygen site in BaO, PrO0.5 and CoO2 layers. Therefore it increases the understanding of the factors influencing oxygen diffusion. For example, it is found that the oxygen occupation fraction in the PrO0.5 layers increases with temperature, while in the CoO2 layers it decreases with temperature. Additionally, the activation enthalpies of oxygen jumps from CoO2 to CoO2, CoO2 to PrO0.5 and PrO0.5 to CoO2 are 0.22 eV, 0.54 eV and 0.34 eV, respectively, exhibiting anisotropic characteristics. Furthermore, the dwell times of oxygen atoms suggest that they are highly mobile in PrO0.5 layers. Combining the analysis of activation enthalpies and dwell times, it is suggested that the oxygen transport is fast within the CoO2 layers while the PrO0.5 layers work as oxygen vacancy reservoirs.

Graphical abstract: A molecular dynamics study of oxygen ion diffusion in A-site ordered perovskite PrBaCo2O5.5: data mining the oxygen trajectories

Back to tab navigation

Publication details

The article was received on 13 Dec 2014, accepted on 03 Feb 2015 and first published on 09 Feb 2015


Article type: Paper
DOI: 10.1039/C4CP05847J
Author version
available:
Download author version (PDF)
Citation: Phys. Chem. Chem. Phys., 2015,17, 7831-7837
  •   Request permissions

    A molecular dynamics study of oxygen ion diffusion in A-site ordered perovskite PrBaCo2O5.5: data mining the oxygen trajectories

    C. Chen, D. Chen and F. Ciucci, Phys. Chem. Chem. Phys., 2015, 17, 7831
    DOI: 10.1039/C4CP05847J

Search articles by author

Spotlight

Advertisements