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["AMARA HAKIM" <hakim.amara@cea.fr>]

Dear abinit users,

I am trying to calculate the physical properties of Co (fcc) which is a 
ferromagnetic material. I have done the convergence studies and followed the 
tutorial about the spin lesson where the case studied is Fe. The problem is 
when I have calculated the total energy for different lattice parameters 
strong discontinuities are present.
I have changed the value of spinat  but the discontinuities are still here. I 
have also the same problem by doing LDA calculations.
You will find in the present mail my input and also the results of the 
calculations.

Is my input wrong  ? Thanks a lot to help me if someone has a good idea.

Sincerely yours,
Hakim Amara


***************************************************************************************
ndtset 20

ecut 65.0    # Maximal kinetic energy cut-off, in Hartree

#Definition of occupation numbers
tsmear 0.003
occopt 4
nband  20

#Spin
nsppol 2
spinat 0.0 0.0 3.0

#Definition of the unit cell
acell:    3*2.77     angstrom    #
acell+    0.061500 0.061500 0.061500  angstrom   #

rprim  0.0  0.5  0.5       
            0.5  0.0  0.5            
            0.5  0.5  0.0            

#Definition of the atom types
ntypat 1          # There is only one type of atom
znucl 27

#Definition of the atoms
natom 1           # There is 1 atom
typat 1           # They both are of type 1, that is, Silicon.

xred             
0.0 0.0 0.0  
                 
#Definition of the k-point grid
kptopt 1         
ngkpt 14 14 14   
nshiftk 4        
shiftk 0.5 0.5 0.5  
           0.5 0.0 0.0  
           0.0 0.5 0.0 
           0.0 0.0 0.5

#Definition of the SCF procedure
nstep 100          # Maximal number of SCF cycles
tolvrs 1.0d-6

#GGA
ixc 11

***************************************************************************************
The result :

  etotal1  -2.6215661695E+01
  etotal2  -2.6282749410E+01
  etotal3  -2.6337522993E+01
  etotal4  -2.6381890117E+01
  etotal5  -2.6417113631E+01
  etotal6  -2.6445629126E+01
  etotal7  -2.6467418836E+01
  etotal8  -2.6499377187E+01
  etotal9  -2.6516464826E+01
  etotal10 -2.6529762903E+01
  etotal11 -2.6539856309E+01
  etotal12 -2.6547220073E+01
  etotal13 -2.6536758079E+01
  etotal14 -2.6541027474E+01
  etotal15 -2.6542119951E+01
  etotal16 -2.6542460630E+01
  etotal17 -2.6540857173E+01
  etotal18 -2.6538315818E+01
  etotal19 -2.6535065872E+01
  etotal20 -2.6531224888E+01