Draw an absorption spectrum using VASP output files

[Jike.Wang]

Dear all,

I want to know how to draw an absorption spectrum using VASP output files. Here are some detail questions:
1. Which file contains the data needed for the spectrum?
2. Can VASPKIT do this directly?

Thanks in advance for your help!

Best regards,
Jike Wang

[henrique_miranda]

This depends on what level of theory you want to use to compute the spectra.
Perhaps this page can help you choose which level of theory you should use:
wiki/index.php/Category:Dielectric_prop ... ion_theory

Assuming the simplest case that is setting LOPTICS=.TRUE. in the INCAR file, you will get the data in vasprun.xml, vaspout.h5 and OUTCAR.

In the OUTCAR it is written under "frequency dependent IMAGINARY DIELECTRIC FUNCTION".

You can also use py4vasp for reading the data from the vaspout.h5 file. You can have a look at section 3.3 in this tutorial:
https://vasp.at/tutorials/latest/response/part1/

If something is not clear don't hesitate to ask!