[Pw_forum] Non Convergence

[Paolo Giannozzi]

Metallic slabs are sometimes difficult to converge.
I tried with mixing_mod='local-TF' (works better for slabs),
a smaller mixing_beta (0.1), a larger degauss (0.05) and a
denser k-point grid (8 8 1) that should yield smoother results,
and it converges, at least for the reduced cutoff (30/300) 
I tried. 

Paolo


Try 
On Wed, 2014-11-05 at 15:41 +0000, Elliot Menkah wrote:
> Hello Everyone,
> I'm running a geometry optimization calculation(relax) of an 11-layer
> Nickel slab and I used the deafult nstep (nstep=50) and electron_maxstep
> (100).
> 
> My system did not converge with the parameters and configurations set as
> it run through 100 iterations.
> 
> Could there be something wrong with the configuration or would I have to
> increase the  electron_maxstep value?.
> 
> Please find attached both input and out files in that regard.
> 
> Thank you
> 
> 
> Kind Regards,
> 
> Elliot
> 
> 
> 
> 
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-- 
 Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
 Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
 Phone +39-0432-558216, fax +39-0432-558222 
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&CONTROL
       title = 'MatStu-ni-001-1x1-11L-Arlxd.in' ,
       calculation = 'relax' ,
       restart_mode = 'from_scratch' ,
       outdir = './tmp' ,
       pseudo_dir = './' ,
       prefix = 'ni-100-1x1-11L-allrlxd',
       tstress = .true. ,
       tprnfor = .true. ,
/
 &SYSTEM
       ibrav = 0,
       nat = 11,
       ntyp = 1,
       ecutwfc = 30,
       ecutrho = 300,
       occupations='smearing',
       smearing='mp',
       degauss=0.05,
       nbnd=60,
       nspin=2,
       starting_magnetization(1)=0.2,
/
 &ELECTRONS
        conv_thr = 1.0D-6,
        mixing_mode = 'local-TF'
        mixing_beta = 0.1,
        electron_maxstep = 50,
/
 &IONS
/
ATOMIC_SPECIES
Ni1 58.6934   Ni.pbe-nd-rrkjus.UPF
ATOMIC_POSITIONS (crystal)
Ni1        0.00000  -0.00000  -0.00000   
Ni1        0.00000  -0.00000   0.11895   
Ni1        0.00000  -0.00000   0.23789   
Ni1        0.00000  -0.00000   0.35684   
Ni1        0.00000  -0.00000   0.47579   
Ni1        0.00000   0.00000   0.59473   
Ni1        0.50000   0.50000   0.05947   
Ni1        0.50000   0.50000   0.17842   
Ni1        0.50000   0.50000   0.29737   
Ni1        0.50000   0.50000   0.41631   
Ni1        0.50000   0.50000   0.53526   
K_POINTS automatic
  8 8 1   0 0 0
CELL_PARAMETERS angstrom
 +2.4904000000  +0.0000000000  +0.0000000000
 +0.0000000000  +2.4904000000  +0.0000000000
  0.0000000000   0.0000000000 +29.6100000000

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