Dear VASP users,
after a DFPT calculation (using VASP.6.4.2), how to plot dispersion curve (based on OUTCAR or vasprun.xml) ? or should we use phononpy ?
Thank you in advance
how to plot phonon dispersion curve
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benali_djebour
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manuel_engel1
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Re: how to plot phonon dispersion curve
VASP supports the calculation of phonon frequencies and eigenvectors via the LPHON_DISPERSION INCAR tag. Since VASP 6.4.2, this properly includes DFPT calculations. You must supply the q-points at which to calculate the phonons in the QPOINTS file. These q-points are given with respect to the primitive cell determined by VASP (see symmetry section in OUTCAR).
We recommend parsing the calculated phonon spectrum from the vaspout.h5 file ("/results/phonons/").
Alternatively, the phonon frequencies are also found in the OUTCAR file ("Phonons" section).
You can control the amount of OUTCAR output with the PHON_NWRITE tag.
If your material is polar, you can set LPHON_POLAR to account for electrostatic interactions (LO-TO splitting). For this, you need to also specify the Born effective charges and the static dielectric tensor.
We recommend parsing the calculated phonon spectrum from the vaspout.h5 file ("/results/phonons/").
Alternatively, the phonon frequencies are also found in the OUTCAR file ("Phonons" section).
You can control the amount of OUTCAR output with the PHON_NWRITE tag.
If your material is polar, you can set LPHON_POLAR to account for electrostatic interactions (LO-TO splitting). For this, you need to also specify the Born effective charges and the static dielectric tensor.
Manuel
VASP developer
VASP developer