# Crystalline LiF
# Generation of the KSS file

# Number of datasets: 2-step calculation
ndtset 2

# Definition of the unit cell: fcc
#acell 3*7.6079786             # Lattice constants (in atomic units)
acell 3*7.7034756             # Lattice constants (in atomic units)

rprim 0.0 0.5 0.5             # FCC primitive vectors
      0.5 0.0 0.5             # (to be scaled by acell)
      0.5 0.5 0.0

# Definition of the system
ntypat 2                      # Number of species
znucl  3 9                    # Z number of each species
natom  2                      # Number of atoms
typat  1 2                    # Type of each atom (index in znucl)
xred   0.00    0.00    0.00   # Reduced coordinates of atom 1
       0.50   -0.50   -0.50   # Reduced coordinates of atom 2

# Definition of the plane-wave basis set
ecut 40.0                     # Kinetic energy cut-off, in Hartree

# Definition of the SCF procedure
nstep 3000                    # Maximum number of SCF cycles

# Step 1: determine the ground state
iscf1    3                    # Algorithm: Anderson mixing of the potential
nband1  10                    # Number of bands
tolwfr1  1.0d-08              # Tolerance on wavefunctions to stop SCF cycles
kptopt1  1                    # Automatic generation of k-points
ngkpt1   8 8 8                # Number of grid points for k-point generation
prtden1  1                    # Store electronic density in a file

# Step 2: obtain the Kohn-Sham band structure
getden2    1                  # Read electronic density from step 1
iscf2     -2                  # Non self-consistent calculation
tolwfr2    1.0d-16            # Tolerance on wavefunctions
nband2    10                  # Number of bands for the system
nbandkss2 50                  # Number of bands to output to the KSS file
kssform2   3                  # Format of the KSS file
kptopt2    1                  # Automatic generation of k-points
ngkpt2     8 8 8              # Number of grid points for k-point generation
symmorphi2 0                  # Disallow non-symmorphic operations (required)
istwfk2    60*1               # Wavefunction storage mode for each k-point