phonopy/example/Si-TURBOMOLE

Si phonon dispersions with TURBOMOLE

The crystal structure in TURBOMOLE format is defined by files "control" and "coord".
This is the default file name scheme for the TURBOMOLE interface and therefore
the parameter "-c control" is not needed

The Si crystal structure is defined with the conventional unit cell (eight atoms).
3x3x3 supercells of the conventional cell are used for the phonon dispersion calculations.
PRIMITIVE_AXES is defined in band.conf to create the phonon dispersions for the primitive cell.

1) Create displaced supercells:
   phonopy --turbomole --dim="3 3 3" -d

   The displaced supercells are created in subdirectories "supercell-NNN".
   Complete TURBOMOLE inputs need to be prepared manually in the subdirectories.
   Please pay special attention on the k-point mesh.
   Use tight SCF convergence criteria such as $scfconv 10
   The following settings in the $riper data group may help convergence:
   pqmatdiag on
   pqsingtol  1.0d-7

2) Run the supercell input with TURBOMOLE or use the pre-calculated data
   in the directory "example-001" (TURBOMOLE 7.3, PBE/SVP):
   cp example-001/* supercell-001

3) Collect forces:
   phonopy --turbomole -f supercell-*

4) Calculate phonon dispersion data into band.yaml and create band.pdf in THz units:
   phonopy --turbomole --dim="3 3 3" -p -s band.conf

   Plot the phonon dispersion in cm^{-1} units:
   (factor = TurbomoleToTHz * THzToCm = 154.10794 * 33.356410)
   phonopy --turbomole --dim="3 3 3" -p -s --factor=5140.48763 band.conf

   Create a formatted plot (here band.yaml is in cm^{-1) units):
   phonopy-bandplot --fmin=0 --line --ylabel="Frequency (cm\$^{-1}\$)" --band-labels "`grep BAND_LABELS band.conf | cut -d= -f2-`" -o dispersion.pdf