Phonopy
Phonopy (Note: please use the develop
branch, rather than the master
branch until the abacus interface has been merged into phonopy’s master
branch.) is a powerful package to calculate phonon and related properties. It has provided interface with ABACUS. In the following, we take the FCC aluminum as an example:
Prepare a ‘setting.conf’ with following tags:
DIM=2 2 2
ATOM_NAME = Al
when three integers are specified after
DIM =
, a supercell elongated along axes of unit cell is createdchemical symbols are specified after
ATOM_NAME =
, number of symbols should matchntype
in ABACUS INPUT file
To obtain supercells (\(2\times 2\times 2\)) with displacements, run phonopy:
phonopy setting.conf --abacus -d
Calculate forces on atoms in the supercells with displacements. For each SCF calculation, you should specify
stru_file
withSTRU-{number}
andcal_force=1
in INPUT in order to calculate force using ABACUS. Be careful not to relax the structures
echo 'stru_file ./STRU-001' >> INPUT
Then create ‘FORCE_SETS’ file using ABACUS inteface:
phonopy -f ./disp-{number}/OUT*/running*.log
Calculate the phonon dispersion:
phonopy band.conf --abacus
using the following band.conf
file:
ATOM_NAME = Al
DIM = 2 2 2
MESH = 8 8 8
PRIMITIVE_AXES = 0 1/2 1/2 1/2 0 1/2 1/2 1/2 0
BAND= 1 1 1 1/2 1/2 1 3/8 3/8 3/4 0 0 0 1/2 1/2 1/2
BAND_POINTS = 21
BAND_CONNECTION = .TRUE.