Format of the pseudopotential files (norm-conserving):
---top of the file---
   **Identifier or 'dft', SEE BELOW
   'Name', Zval, lmax, nlc, nnl, core_corr, lloc, bhstype 
 If nlc=0 and nnl=0                (pseudopotentials in numerical form)
    Zmesh, xmin, dx, nmesh, number_of_wavefunctions
 For l=0,lmax:
   "Comment Line"
   (Vnl(i,l), i=1,mesh)
 End do
 Else if nlc.ne.0 .and. nlc.ne.0   (pseudopotentials in analytical form)
    alpha_loc(1), alpha_loc(2), c_loc(1), c_loc(2)
 For l=0,lmax:
    (alpha_l(i),i=1,3), (a_l(i),i=1,3), (b_l(i),i=1,3)
 End do
 If core_correction: 
    a_nlcc, b_nlcc, alpha_nlcc
 End if
    Zmesh, xmin, dx, nmesh, number_of_wavefunctions
 End if
 For n=0,number_of_wavefunctions:
    "Comment Line"
    l, occupation number
    (chi(i,n), i=1,mesh)
 End do
---bottom of the file---

New format for gradient-corrected pseudopotentials:
the first line contains
'dft'
where dft is a string containing any of the following keywords 
(in any nonconflicting arrangement):

               "sla"    Slater  Exchange                      (default)
               "noexc"  No Exchange
               "nocor"  No Correlation

               "pz"     Perdew-Zunger formula for LDA         (default) 
               "gl"     Gunnarson-Lunqvist
               "hl"     Hedin-Lunqvist
               "pw"     Perdew-Wang
               "vwn"    Vosko-Wilk-Nusair
               "wig"    Wigner
               "lyp"    Lee-Yang-Parr (correl. only)
               "obz"    Ortiz-Ballone (for Perdew-Zunger formula)
               "obw"    Ortiz-Ballone (for Perdew-Wang   formula)

               "nogcx"  No Gradient Correction on exchange    (default)
               "nogcc"  No Gradient Correction on correlation (default)
               "b88"    Becke88  grad.corr. on exchange
               "p86"    Perdew86 grad.corr. on correlation
               "ggx"    GGA on exchange
               "ggc "   GGA on correlation

               "bp"     Becke88+Perdew86  Grad.Corr.
               "pw91"   Perdew-Wang correl. + GGA
               "blyp"   Lee-Yang-Parr functional + Becke88

If **Identifier is found, the Perdew-Zunger LDA is assumed