This example shows how to use the KCW code to compute the band structure
of FCC Silicon. This requires few steps:

1) run a standard scf calculation at PBE level on a regular 2x2x2 mesh. 
   The regular mesh is needed by Wannier90. Ideally you can run scf with 
   symmetry and then a nscf calculation on a regular grid. 
   input=Si.scf.in, output=Si.scf.out

2) perform a separate wannierization for the occupied and empty manifold 
   results in ./wann_occ and ./wann_emp, respectively

3) prepare the KCW calculation 
   input=Si.kcw-wann2kcw.in, output=Si.kcw-wann2kcw.out

4) calculate the screening coefficients 
   input=Si.kcw-screen.in, output=Si.kcw-screen.out

5) calculate, interpolate and diagonalize the KI Hamiltonian 
   input=Si.kcw-ham.in, output=Si.kcw-ham.out

The Si band structure is in Si.kcw_bands.dat.
