Hello

The correct procedure for obtaining IR and Raman in QE is:

1. Firstl perform an Self Consistent Field (scf) calculation with pw.x

2. Calculate the vibrational frequencies (normal modes/phonons) with ph.x

3. Using dynmat.x parse the phonon information from ph.x output

4. again using dynmat.x  parse ph.x output section that contains the spectra data (frequencies and intensities).

Here is an example https://github.com/maxhutch/quantum-espresso/tree/master/PHonon/examples/example15

Konrad

Hi Konrad,

I know that.

I wanted to calculate IR and Raman under a certain electric field, I want to know the input for that.

Shawkat

I run pw.x , ph.x then dynmat.x...

now how can I plot Raman ...??

Dr Vipin Kumar You may find Raman and IR data in the standard output file.

e.g.

$ dynmat.x < input.dynmat > stdout_dynmat

$ awk 'NR==1,/mode/{next}/DYNMAT/,NR==0{next}{print}' stdout_dynmat > plotdata.dat

Dear @Minkyu Park

Can I calculate Raman Peak intensity using qe? Or it only gives peak positions???

Dear Shahran Ahmed Joy this calculation will give you the intensity of the Raman active modes along with its positions.

Dear Guilherme Da Silva Lopes Fabris,can you please share the procedures? Because according

to the procedures similar to example, the calculation gives peak positions only.