Carbon pseudopotential

Reference Konfiguration: $s^2 p^2 d^9$

TITEL  =C:
   LULTRA =        T    use ultrasoft PP ?

   ICORE  =        2    local potential
   RWIGS  =    1.640    wigner-seitz radius

   Description
     l     E      TYP  RCUT    TYP  RCUT
     0   .000      7  1.300    23  1.900
     0  -.700      7  1.300    23  1.900
     1   .000      7  1.200    23  1.900
     1  -.700      7  1.200    23  1.900
     2  -.300      7  1.900    23  1.900

RWIGS is the Wigner Seitz radius if empty spheres of the same size are included for diamond. This radius gives good projection operators for the partial local DOS. NC d-PP is the local potential, s and p are US. This is a very soft PP requiring only 270 eV cutoff, it works well for bulk phases and surfaces. The accuracy can be improved making the cutoffs smaller. We have also used 1.4 instead of 1.9, but results are only marginally effected.