This workflow is designed to help you get started, or improve your workflow using phonopy to calculate a number of exciting properties. This workflow uses a finite difference approach. I have ignored the Density Functional Perturbation Theory approach but more details can be found here: https://phonopy.github.io/phonopy/vasp-dfpt.html.
You must have previously performed convergence tests on your parameters and a geometry optimisation on your structure.
A typical workflow looks like this:
Please go to https://phonopy.github.io/phonopy/vasp.html for more support.
There are only one script needed for this workflow since most of it can be run from the command line:
fd.shdistributes all POSCAR-XXX into single XXX directories with INCAR, KPOINTS, POTCAR, and job script files. I would recommend testing convergence on one structure first and then proceed with all the other ones.
For reference, typical annotated INCAR and KPOINTS files used for a single point calculation are attached. The most important aspects of the INCAR are IBRION = -1 to avoid relaxing the structure, and LREAL = .FALSE. for accurate forces.
Born effective charges describe the electrical polarization induced by the displacement of individual atomic sublattices. They can have a significant impact on phonon properties, such as LO/TO splitting. They can be calculated using the INCAR_born file together with standard input files. Converging Born effective charges typically requires a denser k-point mesh. Typically, a two times increase in all direction is good enough, but good practice involves checking Born effective charges convergence with respect to k-point sampling.
Once the calculation is finished, run phonopy-vasp-born in your working directory and copy and paste the obtained Born effective charges and dielectric constants into a BORN file. Non-analytical term corrections are then calculated in the post-processing (band structure calculation, etc...).
- SUMO to plot phonon dispersions and density of states.
- ASCII-Phonons for animations.
- A comprehensive list of all phonopy setting tags: https://phonopy.github.io/phonopy/setting-tags.html.
- A comprehensive list of all phonopy command line options: https://phonopy.github.io/phonopy/command-options.html.