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[Jan Gryko <gryko@jsucc.jsu.edu>]

 Hello:

 I try to calculate projected density of states for about 
 30 atoms in the unit cell.  Such calculation requires about
 4 GB memory,  therefore  I must use mkmem = 0.  I run a test for 
 Germanium:

 -  first, get SCF wavefunctions (see attached file GeDOSt.in)
 -  second, use the wavefunctions generated above and get projected DOS 
    (see attached GeDOSp.in).
    Everyhing is fine, and the projected DOS is correct, if the
    computations are done "in the memory", i.e. WITHOUT 

     mkmem  0  

   line - please note that  this line is "commented out" in GeDOSp.in.

   Of course, for Ge everything could be done "in the memory",  but
   for a large number of atoms, this is not possible.

   Therefore, I tried using the   mkmem 0   option, just
   by removig  #   in the above line.  In this case
   the projected DOS is exactly ZERO for all angular momenta. 

   Both versions, abinis and abinip  give the same results.
   Did someone have such a problem?  Any comments or hints will be
   greatly appreciated.

   With best regards,
   Jan Gryko
   Jacksonville, AL


     
 
   
#  Ge   
#
#  SCF density computation and DOS


nband   12

ndtset 1

#Dataset 1 : usual self-consistent calculation
kptopt1 1          # Option for the automatic generation of k points,
                   # taking into account the symmetry
ngkpt1  14 14 14   
prtden1  1         # Print the density, for use by dataset 2
toldfe1  1.0d-6
dosdeltae1  0.000734996876
prtdos1   2


#Definition of the unit cell
acell 3*10.6769         
rprim  0.0  0.5  0.5   # FCC primitive vectors (to be scaled by acell)
       0.5  0.0  0.5   
       0.5  0.5  0.0

#Definition of the atom types
ntypat 1
zatnum 32      # Atomic numbers 
                  # possible type(s) of atom. The pseudopotential(s) 
                  # mentioned in the "files" file must correspond
                  # to the type(s) of atom. 
                         

#Definition of the atoms
natom 2          
typat
1
1
xred
0.     0.     0.
0.25   0.25   0.25

#Definition of the planewave basis set
ecut 9.0         # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure
nstep 20          # Maximal number of SCF cycles
diemac 12.0       # 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 prescription for bulk silicon.

   
#  Ge   
#
# use previously computed  SCF density to compute projected DOS


nband   12

ndtset 1


#Dataset 1 : usual self-consistent calculation
irdwfk1  1
kptopt1 1          # Option for the automatic generation of k points,
                   # taking into account the symmetry
ngkpt1  14 14 14   
prtden1  1         # Print the density, for use by dataset 2
toldfe1  1.0d-6
dosdeltae1  0.000734996876
#mkmem    0
natsph   2
iatsph   1 2
ratsph   3.0 3.0
prtdos1   3


#Definition of the unit cell
acell 3*10.6769         
rprim  0.0  0.5  0.5   # FCC primitive vectors (to be scaled by acell)
       0.5  0.0  0.5   
       0.5  0.5  0.0

#Definition of the atom types
ntypat 1
zatnum 32      # Atomic numbers 
                  # possible type(s) of atom. The pseudopotential(s) 
                  # mentioned in the "files" file must correspond
                  # to the type(s) of atom. 
                         

#Definition of the atoms
natom 2          
typat
1
1
xred
0.     0.     0.
0.25   0.25   0.25

#Definition of the planewave basis set
ecut 9.0         # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure
nstep 1          # Maximal number of SCF cycles
diemac 12.0       # 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 prescription for bulk silicon.