phonopy-init command

The phonopy-init command handles the setup steps that happen before phonon calculation:

• generate supercells with displacements (-d, --rd),

• collect calculator results into FORCE_SETS (-f, --fz) or convert them into FORCE_CONSTANTS (--fc),

• inspect the crystal symmetry of the input cell (--symmetry).

After this step, run the phonon calculation with phonopy command.

Examples

VASP:

% phonopy-init -d --dim 2 2 2 --pa auto -c POSCAR-unitcell
% phonopy-init --sp -f vasprun.xml-00{1,2}

Quantum ESPRESSO:

% phonopy-init --qe -d --dim 2 2 2 --pa auto -c NaCl.in
% phonopy-init --sp -f NaCl-00{1,2}.out

Symmetry inspection:

% phonopy-init --symmetry -c POSCAR-unitcell

Random displacements with a finite snapshot count:

% phonopy-init --rd 100 --dim 2 2 2 --pa auto -c POSCAR-unitcell

Finite-temperature random displacements require phonon information and belong to the phonon-calculation step, so they are handled by phonopy command rather than phonopy-init.

Relation to the legacy phonopy command

Earlier versions of phonopy used a single phonopy command to cover both the setup and the phonon-calculation steps. The two responsibilities have been split:

Old invocation	New invocation
phonopy -d --dim ... -c POSCAR	phonopy-init -d --dim ... -c POSCAR
phonopy --sp -f vasprun.xml*	phonopy-init --sp -f vasprun.xml*
phonopy --symmetry -c POSCAR	phonopy-init --symmetry -c POSCAR
phonopy-load --band auto ...	phonopy --band auto ...

The new phonopy command rejects setup flags (-d, --rd, -f, --fz, --fc, --symmetry) and points the user to phonopy-init.