Hi all, could anyone provide some examples or tips on how to use the ferroelectricity.polarization module properly. Although I can get some information from the link below, the exact procedure seems complicated. I have also searched the previous forum posts and there doesn’t seem to be any discussion on this.
https://pymatgen.org/pymatgen.analysis.ferroelectricity.polarization.html
Yes, it is complicated. If you haven’t read Spaldin’s paper on the modern theory of polarization, that will shed some light on the situation. Basically you need to make a set of structures interpolated from the polar structure to a non-polar reference phase. Here’s a discussion of some of the practical issues in making these structures. Once you have done the calculations, you can then generate a Polarization object using from_outcars_and_structures, then use get_same_branch_polarization_data to get the polarization.
However, I’d recommend doing the branch fitting manually with a spreadsheet and scatter plot the first time, just so you understand how it works and can verify that you’re getting the right answer with Pymatgen.
Ok, thank you very much.