How to calculate the Phonon Band Structure using the Phonopy code using Script

Phonopy code is developped to calculate the phonon and thermal properties plus some other functionalities.

To install the code click on the following link:

How to install Phonopy Code to calculate Phonon and Thermal properties

 

 We will calculate the Band structure of Silicon. We need only the pseudopotential and one script

 

Pseudopotential

Si.psf

run_example.sh

Commands to run this example:

head="
SystemName          silicon
SystemLabel         Si

NumberOfSpecies     1

%block ChemicalSpeciesLabel
 1  14  Si
%endblock ChemicalSpeciesLabel

PAO.BasisSize       sz

MeshCutoff         400.0 Ry

MaxSCFIterations    50
DM.MixingWeight      0.2
DM.NumberPulay       3
DM.Tolerance         1.d-4
DM.UseSaveDM

SolutionMethod       diagon

WriteForces          .true.

ElectronicTemperature  100 K

AtomicCoordinatesFormat  Fractional
"

kgrid_uc="
%block kgrid_Monkhorst_Pack
   8   0   0  0.0
   0   8   0  0.0
   0   0   8  0.0
%endblock Kgrid_Monkhorst_Pack
"

kgrid_sc="
%block kgrid_Monkhorst_Pack
   3   0   0  0.0
   0   3   0  0.0
   0   0   3  0.0
%endblock Kgrid_Monkhorst_Pack
"

atoms_uc="
NumberOfAtoms       2
LatticeConstant     5.430 Ang
%block LatticeVectors
  0.000  0.500  0.500
  0.500  0.000  0.500
  0.500  0.500  0.000
%endblock LatticeVectors

%block AtomicCoordinatesAndAtomicSpecies
    0.00    0.00    0.00   1 #  Si  1
    0.25    0.25    0.25   1 #  Si  2
%endblock AtomicCoordinatesAndAtomicSpecies
"

echo "$head" > Si.fdf
echo "$kgrid_uc" >> Si.fdf
echo "$atoms_uc" >> Si.fdf
phonopy --siesta -d --dim="3 3 3" -c Si.fdf --amplitude=0.04
mkdir disp-001
cp Si.psf supercell-001.fdf disp-001
cd disp-001
echo "$head" > Si.fdf
echo "$kgrid_sc" >> Si.fdf
echo "LatticeConstant 1.0 Bohr">> Si.fdf
echo "%include supercell-001.fdf" >> Si.fdf
siesta < Si.fdf
cd ..
phonopy --siesta -f disp-001/Si.FA -c Si.fdf
cat > band.conf << EOF
ATOM_NAME = Si O
DIM =  3 3 3
BAND_POINTS = 100
BAND = 1/2 1/2 1/2  0.0 0.0 0.0  0.0 1/2 1/2  1.0 1.0 1.0
EOF
phonopy --siesta -p band.conf -c Si.fdf

Calculation and plotting

 

% conda activate phonopy

(phonopy) % chmod +x run_example.sh