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dft_inputs [2016/12/08 08:40]
krejcio created
dft_inputs [2017/01/26 14:58] (current)
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-Hartree potential that may serve as an input for the PPM can be produced by various DFT codes. Here we show examples, for couple of them:+Hartree potential that may serve as an input for the PPM can be produced by various DFT codes. A slab calculations are necessary for a creation of the Hartree potential. The calculated system should be in the lower part of the unit cell, but z coordinates of the top-most layer has to be above zero! At least 10 Ǎ of vacuum above a slab geometry has to be used. 15-20 Ă of Vacuum are recommended. Here we show examples ​how to produce a hartree potential, for couple of DFT codes:
  
 == Fireball == == Fireball ==
  
-fireball.in for creation of an fftpot.xsf file with Hartree potential with using a McWEDA functional should look like:+__fireball.in__ for creation of an __fftpot.xsf__ file with Hartree potential with using a McWEDA functional should look like:
  
 +  &OPTION
 +  basisfile =     '​answer.bas'​
 +  lvsfile =       '​input.lvs'​
 +  kptpreference = '​input.kpts'​
 +  nstepf ​    = 1
 +  icluster ​  = 0
 +  itdse      = 0
 +  iqout      = 1
 +  ifixcharge = 1     ! 0 if you don't have pre-calculated atomic charges in CHARGES
 +  iquench ​   = -1
 +  &END
 +  ​
 +  &OUTPUT
 +  iwrtxsf = 1   ! print the important file
 +  iwrtden = 1   ! print the important file
 +  &END
 +  ​
 +  &MESH
 +  ifixg0 = 1            ! 
 +  g0     = 0.0,​0.0,​0.0 ​ ! do not shift the position of atoms in fftpot.xsf with respect to the answer.bas
 +  Ecut = 300.0d0 ​       ! not really necessary, but gives grid sampling approximately 100 pm.
 +  &END
 +
 +A __fireball.in__ file for calculations with XC on a grid computations:​
 +
 +  &OPTION
 +  basisfile ​    = '​answer.bas'​
 +  lvsfile ​      = '​input.lvs'​
 +  kptpreference = '​samplek.kpts'​
 +  nstepf ​    = 1
 +  icluster ​  = 0
 +  itdse      = 0
 +  iqout      = 1
 +  ifixcharge = 0
 +  dt         = 0.5
 +  iquench ​   = -1
 +  iks        = 1
 +  imcweda ​   = 0
 +  idogs      = 0
 +  bmix       = 0.05
 +  &END
 +  ​
 +  &OUTPUT
 +  iwrtxsf = 1   ! print the important file
 +  iwrtden = 1   ! print the important file
 +  &END
 +  ​
 +  &MESH
 +  ifixg0 = 1            ! 
 +  g0     = 0.0,​0.0,​0.0 ​ ! do not shift the position of atoms in fftpot.xsf with respect to the answer.bas
 +  Ecut = 300.0d0 ​       ! not really necessary, but gives grid sampling approximately 100 pm.
 +  &END
 +
 +== VASP  ==
 +
 +[[http://​www.vasp.at/​]]
 +
 +A __LOCPOT__ file containing the Hartree potential is produced during standart //VASP// run. One just have to care about a dipole correction (if necessary). The __LOCPOT__ file has to be convert into an *.xsf file, eg. via [[http://​theory.chm.tu-dresden.de/​~jk/​software.html]]
 +
 +== FHI-AIMS ==
 +
 +
 +[[http://​aimsclub.fhi-berlin.mpg.de/​]]
 +
 +Add following sequention into your __control.in__ file:
 +
 +  output cube hartree_potential
 +    cube origin lx ly lz
 +
 +where lx, ly & lz are shifting the output cube file so the written grid would be at the beginning of the Cartesian system. PPM can now read geometry from a cube file created by //​FHI-AIMS//​ and shift it according to the shift of the cube cell; however for good run of the PPM calculation at least lz has to be properly specified. l = length of lattice vector / 2 - 0.05; But proper shift is used only, when the lattice vector follows some Cartesian direction.
  
dft_inputs.1481182809.txt.gz · Last modified: 2016/12/08 08:40 (external edit)