phonopy/example/NaCl-QE

This is an example of QE-PW interface.

To create supercells with displacements:

% phonopy --qe -c NaCl.in -d --dim="2 2 2"

A perfect 2x2x2 supercell (supercell.in) and two 2x2x2 supercells
(supercell-xxx.in) of the conventional unit cell written in NaCl.in
are created. In addition, disp.yaml file is created. After force
calculations with the crystal structures in supercell-xxx.in, it is
needed to create FORCE_SETS file by

% phonopy --qe -f NaCl-001.out NaCl-002.out

Here .out files are the output of the PW calculations and are
supposed to contain the forces on atoms calculated by PW. The
disp.yaml file has to be put in the current directory. Now you can run
phonon calculation, e.g.,

% phonopy --qe -c NaCl.in -p band.conf

Non-analytical term correction can be applied using --nac option by

% phonopy --qe --nac -c NaCl.in -p band.conf

BORN file is created running DFPT calculation using ph.x (phonon) code in the quantum espresso package. The details of howto are found in the phonopy documentation. The input and output files of the ph.x DFPT calculation are NaCl.ph.in and NaCl.ph.out.