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[mmikami@rc.m-kagaku.co.jp]

I think that I had similar experiences when I set small nline (say, 
three)  in some cases ... (Sorry, I cannot remember which kind of jobs 
.... I think that they might be "metallic" systems.)  They were managed 
by increasing larger nline (say, five or six ... the present default 
value for nline is four) At that time, I had not change iscf  (default 
value of five). Thus I think that the increase of  nline could also 
help in some cases. (It might not always work ...)

The FAQ will be updated. Merci beaucoup, Matthieu.

Regards,
Masayoshi

On 2003.8.20, at 21:12 Asia/Tokyo, verstraete@pcpm.ucl.ac.be wrote:

> No, rather use iscf 3
>
> the default iscf 5 is faster but doesn't work well for complicated 
> cases.
> iscf 3 is more robust. This should be in the FAQ or in the definition 
> of
> iscf. Everyone has the same problem. It's possible that increasing 
> nband
> can work (test it!) but in some cases it won't.
>
> Matthieu
>
> On Wed, 20 Aug 2003, James Raynolds wrote:
>
> >         Increase the value of "nband".
> >
> >
> > -----Original Message-----
> > From: homegchiche@yahoo.fr [mailto:homegchiche@yahoo.fr]
> > Sent: Wednesday, August 20, 2003 8:02 AM
> > To: forum@abinit.org
> > Subject: [abinit-forum] Nickel GGA simulation
> >
> >
> > Dear Abinit users,
> > I have some problems in the GGA studies of  Bulk Nickel,  the calculs 
> > are
> > not converge, I have got this error message :
> >  findmin : WARNING -
> > (scfcge) The second derivative is negative, equal to 
> > -4.3426189766E-05.
> > findmin : lambda_predict  -3.0200E+00 etotal_predict  
> > -3.1416489113E+01
> > scfcge : ERROR -
> > Potential-based CG line minimization not converged after 13 restarts.
> > Action : read the eventual warnings about lack of convergence.
> > Some might be relevant. Otherwise, raise nband.
> > leave_new : decision taken to exit ...
> >
> >  my input files is :
> >
> > strprecon 0.1
> >  ndtset 2
> >  getwfk2 1
> >  acell 3*6.6496
> >  rprim  0.0  0.5  0.5
> >         0.5  0.0  0.5
> >         0.5  0.5  0.0
> >  ntype 1
> >  zatnum 28.0
> >  natom 1
> >  type  1
> >  xred 0.0 0.0 0.0
> >  nsppol 2
> >  spinat 0.0 0.0 0.5
> >  optcell 1
> >  ionmov  3
> >  nstep  60
> >  ntime  1000
> >  toldfe 1.0d-6
> >  ecut 50.0
> >  ixc  11
> > occopt 7
> >  tsmear 0.01
> >  nband 6
> >  kptopt 1
> >  ngkpt  4 4 4
> >  nshftk 1
> >  shiftk
> >  0.5 0.5 0.5
> >
> > The input files to generate the pseudopotentiel is :
> >
> > 28.00  5  3  6  1.00 : z  nc  nv iexc rnlc
> >     1  0   2.00      : n  l   f
> >     2  0   2.00
> >     2  1   6.00
> >     3  0   2.00
> >     3  1   6.00
> >     3  2   8.00
> >     4  0   2.00
> >     4  1   0.00
> > 2  t                 : lmax  s_pp_def
> > 0  2.10 0.0 t
> > 1  2.91 0.0 t
> > 2  2.08 0.0 t
> >
> > i wait your help and thanks for your times
> > Megchiche
>
> --
> ===================================================================
> Matthieu Verstraete               mailto:verstraete@pcpm.ucl.ac.be
> PCPM, Boltzmann, pl. Croix du Sud, 1            tel: 010/ 47 86 81
> B-1348 Louvain-la-Neuve  Belgium                fax: 010/ 47 34 52