mirror of https://github.com/phonopy/phonopy.git
38 lines
1.4 KiB
Markdown
38 lines
1.4 KiB
Markdown
This is example of PHONOPY calculations using CP2K including BORN charges calculations.
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The example is tested with version 8 and 2024.1.
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First one have to construct structures with displacements stored in xyz file format.
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Use --born option if BORN charges calculations required.
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```bash
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% python gen_supercell_xyz.py -i Punitcell.inp --dim="2 2 2" --born
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```
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Lattice parameters are printed in the output and in each supercell.xyz structure. Put
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lattice parameters in force.inp pattern file. Edit the file according to your
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calculations (Potentials, cutoff energy and so on). Edit path where potential files
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are stored (@SET BASISDIR /home/USER/cp2k/Potentials in force.inp).
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Check parameters in polar.inp correspond to parameters in force.inp.
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Linear response calculations (polar.inp) require tight convergence
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```EPS_SCF 1.0E-8``` recomended.
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Generate directories using ```make_displ_dirs.sh``` bash script, then run CP2K
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calculations.
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To speed up the process make calculations for ideals structure (DISP-0000 dir) first,
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then copy WFN file in all DISP directories to use as initial guess.
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Collect forces after CP2K calculations is done:
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```bash
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%phonopy --cp2k -f DISP-{0001..0012}/SiO2-forces-1_0.xyz
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```
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Generate BORN file to take non-analitical term into account:
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```bash
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python get_born_cp2k.py -i DISP-0000/polar.out -m force.out
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```
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Plot bandstrucutre
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```bash
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phonopy --cp2k -c Punitcell.inp --dim="2 2 2" --band=auto -s -p --factor=3739.4256801 --nac
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```
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