# Crystalline BaTiO3: 
    prtwf   0
   prtden   0

   ndtset   1


     nqpt   1            # One qpt for each dataset (only 0 or 1 allowed)
                         # This is the default for all datasets and must
                         #  be explicitly turned off for dataset 1.

     qpt  0.5 0.5 0.5

   irdwfk   1          # Use GS wave functions from dataset1
   kptopt   3          # Need full k-point set for finite-Q response
   rfphon   1          # Do phonon response
  rfatpol   1 5        # Treat displacements of all atoms
    rfdir   1 1 1      # Do all directions (symmetry will be used)
   tolvrs   1.0d-8     # This default is active for sets 3-10


#Definition of the k-point grid
ngkpt  8 8 8
nshiftk 1
shiftk 0.5 0.5 0.5

#######################################################################
#Common input variables

#Definition of the unit cell
   acell 3*7.5323692530
   rprim  1 0 0
          0 1 0
          0 0 1

#Definition of the atom types
   ntypat 3
    znucl 56 22 8

#Definition of the atoms
natom 5
typat 1*1 1*2 3*3
xred
  0.0 0.0 0.0
  0.5 0.5 0.5
  0.0 0.5 0.5
  0.5 0.0 0.5
  0.5 0.5 0.0

#Gives the number of band, explicitely (do not take the default)
    nband   20

#Exchange-correlation functional

      ixc 23

#Definition of the planewave basis set

     ecut  60.0        # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure (dummy)
     iscf   5          # Self-consistent calculation, using algorithm 5
    nstep   70         # Maximal number of SCF cycles
   diemac   9.0        # Although this is not mandatory, it is worth to
                       # precondition the SCF cycle. The model dielectric
                       # function used as the standard preconditioner
                       # is described in the "dielng" input variable section.
                       # The dielectric constant of AlAs is smaller that the one of Si (=12).