# Crystalline AlAs : computation of the set of q point needed 
# for the Fourier interpolation

  kptopt   1            # Automatic generation of different k point sets, taking
                        # into account the symmetry

  ngkpt  6 6 6
 
  nshftk 1
  shiftk 0.5 0.5 0.5
  prtvol 1 
 
# Note the dummy values of nstep and nline
    nstep   1         # Maximal number of SCF cycles
    nline   1         # Maximal number of SCF cycles

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

#Definition of the unit cell
    acell   3*7.9076215129
    rprim   1.0  0.0  0.0   # In lessons 1 and 2, these primitive vectors
            0.0  1.0  0.0   # (to be scaled by acell) were 1 0 0  0 1 0  0 0 1
            0.0  0.0  1.0   # that is, the default.

#Definition of the atom types
   ntypat   2         # There are two types of atom
    znucl   55 17     # The keyword "znucl" refers to the atomic number of the 
                      # possible type(s) of atom. The pseudopotential(s) 
                      # mentioned in the "files" file must correspond
                      # to the type(s) of atom. Here, type 1 is the Aluminum,
                      # type 2 is the Arsenic.

#Definition of the atoms
    natom   2         # There are two atoms
    typat   2 1       # The first is of type 1 (Al), the second is of type 2 (As).
                       
     xred   0.0  0.0  0.0
            0.5  0.5  0.5  

#Gives the number of band, explicitely (do not take the default)
    nband   12         

#Exchange-correlation functional

      ixc   1             # LDA Teter Pade parametrization

#Definition of the planewave basis set

     ecut   3.0           # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure (dummy)
     iscf   5          # Self-consistent calculation, using algorithm 5
   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).
  tolvrs    1.0d-18    # SCF stopping criterion (dummy)