Alpha-AlF3

Exercise : Determine the ²⁷Al C_q value and the Al and F schieldings.

INCAR

  SYSTEM      =  Al F3

  GGA          = PE
  ISTART       = 1
  ICHARG       = 0
  INIWAV        = 1
  LREAL        =  AUTO
  ISYM         = 2
  ISPIN        = 1

Ionic minimisation
  NSW         = 0
  ISIF          = 2
  IBRION        = 2
#  EDIFFG       = -2E-2
  POTIM        = 0.1

Electronic minimisation
  IALGO        = 38

  LWAVE        = .TRUE.

  EMIN         =   -20.0
  EMAX         =   10.0
  NEDOS        = 1601

EFG Calculation
  LEFG         = .TRUE.
  QUAD_EFG     = 146.6 0.0

Chemical Shift
  PREC         = Normal    # nice
  ENCUT        = 400.0      # typically higher cutoffs than usual are needed
  ISMEAR = 0; SIGMA= 0.1 # no fancy smearings, SIGMA sufficiently small
  EDIFF        = 1E-9      # you'd need much smaller EDIFFs.

  LCHIMAG      = .TRUE.   # to switch on linear response for chemical shifts
  DQ           = 0.001         # often the default is sufficient
  ICHIBARE     = 1       # often the default is sufficient
  LNMR_SYM_RED = .TRUE. # be on the safe side
  NSLPLINE     = .TRUE.  # only needed if LREAL is NOT set.
  LREAL        = A          # helps for speed for large systems, not needed
  NBANDS       = 25       # to safe memory, ??? = NELECT/2

KPOINTS

automatic mesh
0
Auto
20

POSCAR

Al1 F3
1.0
        4.9305000305         0.0000000000         0.0000000000
        2.4652500153         4.2699382798         0.0000000000
        2.4652650832         1.4233214594         4.1486879977
   Al    F
    2    6
Direct
     0.000000000         0.500000000         0.000000000
     0.500000000         0.000000000         0.500000000
     0.177499995         0.250000000         0.750000000
     0.822499990         0.750000000         0.250000000
     0.677500010         0.322499990         0.250000000
     0.322499990         0.677500010         0.750000000
     0.250000000         0.177499995         0.250000000
     0.750000000         0.822499990         0.750000000

Download

Ni111clean_400eV.tgz

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