The ABINIT Users Mailing List ( CLOSED )

["Anglade Pierre-Matthieu" <anglade@gmail.com>]

PS:
Someone (who wants his name kept undisclosed) comfirmed my feeling
that your system may be too much out of equilibrium for Abinit.
Although this is clearly an Abinit bug it may be difficult to correct.
When the bug is triggered the xorkaround is to start again from the
previous position.

Also, I have noticed that CG (BFGS) gets totaly lost for your ion
optimisation. Using Quenched molecular dynamic for startup (ionmov 7)
would undoubtely lead to better results.


Regards

PMA


On 9/2/07, Anglade Pierre-Matthieu <anglade@gmail.com> wrote:
> Hi,
>
> Sorry for the long latency. I have not a lot of ideas about the
> reasons for the bug you see. Moreover your case is quite time
> consuming.
>
> I have observed a few things I find a bit weird in your input. Maybe
> correcting those would lead to better results.
> First I must say that I run your case with troullier-martins pseudo
> potentials. For those the ecut you use is too low. And energy wanders
> along minimization steps instead of decreasing.
> I am very surprised by the large value you set for dilatmx in the
> second dataset.  It would not be very surprising that a bug never
> encountered before happens if your cell varies by more than 100%. May
> be a workaround would be to have cell parameters allowing smaller
> values for dilatmx ?
> Also, your calculation converge very slowly yet poses no problems in
> term of non-SCF convergence. Why not decreasing nline a little bit.
> And why not using a more efficient preconditioner. Moreover, for an
> energy minimization, the sensible convergence criterion is forces not
> potential residuals. You may save half the SCF steps whose cost will
> be decreased by a factor of two...
>
> Regards
>
> PMA
>
> On 8/31/07, duan_semi <abinit_duan@126.com> wrote:
> >
> > Dear all,
> >          When I optimize the structure of PbTiO_3 with different strains
> > along c-axis, the c-axis  is  orthogonal to the a-b plane.  the attached
> > file is my input file. I find that when strains are larger than a value,
> > the following error always appears:
> >   wfsinp : enter
> > -P-0000  initwf : disk file gives npw=  6563 nband=    22 for k pt number=
> >  1
> > -P-0000  initwf :    22 bands have been initialized from disk
> > -P-0000  initwf : disk file gives npw=  6541 nband=    22 for k pt number=
> >  2
> > -P-0000  initwf :    22 bands have been initialized from disk
> > -P-0000  initwf : disk file gives npw=  6527 nband=    22 for k pt number=
> >  3
> > -P-0000  initwf :    22 bands have been initialized from disk
> > -P-0000  leave_test : synchronization done...
> >  wfsinp: loop on k-points and spins done in parallel
> >  pareigocc : MPI_ALLREDUCE
> > -P-0000  leave_test : synchronization done...
> >  wfsinp: loop on k-points done in parallel
> > -P-0000 - newkpt: read input wf with ikpt,npw=   1    6563, make ikpt,npw=
> > 1  148270
> > -P-0000
> > -P-0000  sphereboundary: BUG -
> > -P-0000   iloop,igb,mgb=       2     125     124
> > -P-0000   about to overwrite gbound.
> > -P-0000
> > -P-0000  leave_new : decision taken to exit ...
> > -P-0000  leave_new : synchronization done...
> > -P-0000  leave_new : exiting...
> >
> >       Any suggestion will be helpful!
> > Thanks!
> > DWei
> >
> >
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> >
>
>
> --
> Pierre-Matthieu Anglade
>


-- 
Pierre-Matthieu Anglade