Thermal lines and special displacements with YamboPy
THIS TUTORIAL IS FOR INTERNAL USE ONLY
In this tutorial we show how to generate Thermal Lines[1]. and Special Displacements[2] with YamboPy and then use them
to calculate different properties at finite temperature.
We will start from phonon calculations, interpolation of phonon modes, generation
of thermal lines/special displacements supercells and finally calculation of electronic properties ad finite temperature.
This tutorial requires a deep knowledge of phonon calculations, and the study of Refs.[1],[2].
Phonons
Phonon calculation
In order to generate Thermal-lines or Special Displacements we need a converged phonon calculation. We will take as example bulk Diamond.
In the file Diamond_Phonons.tgz you will find all inputs to generate phonon band
structure report below:
Notice that calculations are not fully converged but the selected parameters are enough to get positive and reasonable phonons for the Diamond.
Phonon interpolation in the BZ
Now that you calculated phonons, you have to interpolate them on a regular grid in the full Brillouin zone, that later will be used to general supercells and displace atoms.
Thermal-lines/Special Displacements
References
- ↑ 1.0 1.1 Vibrational averages along thermal lines, Bartomeu Monserrat, Phys. Rev. B 93, 014302 (2016)
- ↑ 2.0 2.1 Theory of the special displacement method for electronic structure calculations at finite temperature, Marios Zacharias, Feliciano Giustino, Phys. Rev. Research 2, 013357 (2020)