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[Xavier Gonze <xavier.gonze@uclouvain.be>]

Hi Hakim,

You should use the ecutsm input variable ... (e.g.  0.5 Ha)
Xavier

On 09 Mar 2009, at 10:03, AMARA HAKIM wrote:

> 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