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[Keitel <kacsssj@gmail.com>]

Hi people,

I am newer in Abinit issues so forgive my silly questions.
I am trying to optimize the ecut for an Fe-Fe molecule, but
it lasts too much i guess and the convergence threshold
will never reach. The SCF steps are 200, and the energy
seem to not converge.

At the end I show my .in.
Any theoretical (that is books) and technical (ticks) recommendations
are always welcome.

Thanks in advance

# iron dimer
#Define the different datasets

prtgeo 15 # more than 1
ndtset 10
udtset 5 2

chkprim 0
dilatmx 1.2

#Definition of the unit cell
acell 16 16 16    # The keyword "acell" refers to the
                  # lengths of the primitive vectors (in Bohr)
ecut:? 15    ecut+? 5

rprim 1 0 0  0 1 0  0 0 1 # This line, defining orthogonal primitive vectors,
                          # is commented, because it is precisely the default
value of rprim

#Definition of the atom types
ntypat 1          # There is only one type of atom
znucl 26           # 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, the only type is Hydrogen.
                         
#FIRST DATASET 2 ATOMS
natom?1 2
ionmov?1  3
ntime?1  30
tolmxf?1  5.0d-4
xcart?1  -1.9 0.0 0.0 
          1.9 0.0 0.0
ecutsm?1 0.5 
toldff?1  5.0d-5 
nband?1    10  


#SECOND DATASET 1 ATOM
natom?2 1
nsppol?2 2   #spin polarized calculation
nband?2 10
toldfe?2 1.0d-6
xcart?2  0.0 0.0 0.0
spinat?2 0.0 0.0 1.0 
ecutsm?2 0.5 

typat  1 1        


#Definition of the k-point grid
kptopt 0          # Enter the k points manually 
nkpt 1            # Only one k point is needed for isolated system,
                  # taken by default to be 0.0 0.0 0.0

#Definition of the SCF procedure
nstep 200          # Maximal number of SCF cycles

diemac 1.0d+6        # 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.
                  # Here, we follow the prescriptions for molecules
                  # in a big box

ixc 8