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[guillermo.roman@uam.es]

I am new in abinit.
I am trying to calculate the Total Energies. I have to use 25 Hartrees and a 
20 Ang cubic cell. 
I get a "segmentation fault just before having calculated the first Etotal.
I though it was a problem of memory, so I reduce the parameters (ecut, acell) 
and I get a positive result. However, using these less demanding parameters I 
do a monitoring of the memory cost. I am runing in a Intel Xeon 64 dual core 
with 4Gb of memory. With 12.5 Ha and 40 bohr cubic cell I get a "segmentation 
fault" while abinit print:
P This job should need less than                     532.428 Mbytes of memory.
  Rough estimation (10% accuracy) of disk space for files :
  WF disk file :     34.002 Mbytes ; DEN or POT disk file :     16.002 Mbytes.

So, it seems that it is not a memory problem at all. 

I am running a sequencial 5.4.4 version (I have tried 5.3 too)
the only WARNING I receive is related with low ecut I am using:
mkdenpos : WARNING -
  Density went < 0 at     36827 points
  and was set to  1.00E-14.  Lowest was  -0.90E-05.
  Likely due to too low boxcut or too low ecut for pseudopotential core 
charge.


I almost sure is a detail or something that it's missing in th input file

--------------------------------------------------------------
Here is easy the Input file:

# C6H6 molecule in a big box
#
#Definition of the unit cell
acell 40.0 40.0 40.0 
                        
#Definition of the atom
ntypat 2         
znucl 1 6         
natom 24           
typat 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2
xangst
-2.5253  0.0064  0.0005     
-1.2742  2.1434  0.0006     
 1.2021  2.1407  0.0005     
 2.4309 -0.0086  0.0005     
 1.1848 -2.1480  0.0005     
-1.2911 -2.1403  0.0005     
-2.5253  0.0064  7.0005     
-1.2742  2.1434  7.0006     
 1.2021  2.1407  7.0005     
 2.4309 -0.0086  7.0005     
 1.1848 -2.1480  7.0005     
-1.2911 -2.1403  7.0005     
-0.7367  1.2078  0.0005     
 0.6606  1.2074  0.0005     
 1.3519 -0.0065  0.0005     
 0.6470 -1.2126  0.0005     
-0.7500 -1.2068  0.0005     
-1.4463  0.0044  0.0005     
-0.7367  1.2078  7.0005     
 0.6606  1.2074  7.0005     
 1.3519 -0.0065  7.0005     
 0.6470 -1.2126  7.0005     
-0.7500 -1.2068  7.0005     
-1.4463  0.0044  7.0005     
      
#Ionic Relaxation            
#ionmov       4           #ionic relaxation by Cradient Conjugated
optcell      0               #optimize the cell shape and dimensions
#ntime       50
#tolmxf      5.0d-5       #hartree/Bohr

#SFC options
ixc         11                #PBE
iscf         17               #Pulay scheme for mixing SFC history (tried 
with 5 also)
#npulayit     3           #number of pulay
iprcel       0                #SFC precondition scheme Default
nsppol       1             #number of spin polarization

#Definition of the SCF procedure
nstep 30             #  SCF cycles
toldfe 1.0d-6     
 diemac 2.0         
 
#Definition of the planewave basis set
ecut 25.0 Ry        

#Definition of the k-point grid
nkpt 1            # Only one k point is needed for isolated system,

#Debugging options
prtvol 1
istatr 5