[Wien] Problems with PORT minimization!
L. D. Marks
L-marks at northwestern.edu
Tue Oct 19 10:05:11 CEST 2004
Please attach your case.outputM file (and for reference your case.struct
file).
On Mon, 18 Oct 2004, Timo Jacob wrote:
> > The "***false convergence***" means that the algorithm could not find a
> > location with a better energy consistent with the forces that you are
> > giving it. This may not be an issue, since the numerical accuracy of
> > the energies and forces in Wien is limited. Unfortunately you don't
> > provide all the information that is needed to diagnose your problem:
> > 1) Are your energies/charges etc well converged?
> Yes, they are well converged. Before running mini I always perform a full SCF
> run with -cc 0.0001. After that I calculate the forces with the propriate
> corrections.
> > 2) Is it a CXZ spacegroup (in which case there are other problems)
> It is a hexagonal surface unitcell, Pt(111).
> >
> > Beyond this, there is a basic point. You have fixed the positions of your
> > central Pt atoms, so it is quite reasonable that the forces do not go to
> > zero at the (constrained) energy minimum.
> Since there is only a single atom in each layer (1x1 surface unit cell), this
> should not affect. Besides an avoided translation (in z-direction) of the
> entire slab, the system should be able to achieve his global minimum. The
> only real constraint is given by the symmetry, which fixes the x and y
> coordinates. Thus, I only checked the z-components of the force-vectors.
>
> Thanks,
> Timo.
>
> >
> > On Mon, 18 Oct 2004, Timo Jacob wrote:
> > > Hello,
> > >
> > > I try to otimize the structure of a 5 layer slab (1x1) including 3
> > > central Pt layers and an oxygen layer at each surface.
> > > For my calculations I use an energy cutoff of 15 Ry (for an initial
> > > structure optimization) and the central Pt layer is fixed during the
> > > geometry optimization.
> > > Using the PORT option with the *.inM input attached below,
> > > the total energy mostly decreases but the forces seem to converge to
> > > finite numbers
> > >
> > > :FOR002 -38.535
> > > :FOR003 16.344
> > >
> > > and after 3-4 geometry iterations with same forces the geometry
> > > optimization stops with stop_forces_small. However, *.outputM contains
> > > the line ****false convergence*****.
> > >
> > > Any suggestions?
> > >
> > > Thanks in advance.
> > >
> > > ------------- *.inM -------------
> > > PORT 2.0
> > > 0 0 0 1.0
> > > 1.0 1.0 1.0 1.0
> > > 1.0 1.0 1.0 1.0
> > > ----------------------------------
> > >
> > > ------------ *.in1 ---------------
> > > WFFIL (WFPRI, SUPWF)
> > > 3.900000 10 4 (R-MT*K-MAX; MAX L IN WF, V-NMT
> > > -.22515 6 0 global e-param with N other choices, napw
> > > 0 -0.407 0.000 CONT 1
> > > 1 -0.226 0.000 CONT 1
> > > 1 -3.803 0.000 CONT 1
> > > 2 -0.167 0.000 CONT 1
> > > 3 -0.176 0.000 CONT 1
> > > 3 -4.858 0.000 CONT 1
> > > -.22515 7 0 global e-param with N other choices, napw
> > > 0 -0.452 0.000 CONT 1
> > > 1 -0.283 0.000 CONT 1
> > > 1 -3.872 0.000 CONT 1
> > > 2 -0.240 0.000 CONT 1
> > > 2 -1.471 0.000 CONT 1
> > > 3 -0.212 0.000 CONT 1
> > > 3 -4.930 0.000 CONT 1
> > > -.22515 3 0 global e-param with N other choices, napw
> > > 0 -0.367 0.000 CONT 1
> > > 0 -1.468 0.000 CONT 1
> > > 1 -0.292 0.000 CONT 1
> > > K-VECTORS FROM UNIT:4 -9.0 2.5 emin/emax window
> > > ----------------------------------
> > >
> > >
> > > --
> > > Dr. Timo Jacob Phone : ++49-30-8413 4816
> > > Fritz-Haber-Institut Fax : ++49-30-8413 4701
> > > der Max-Planck-Gesellschaft
> > > Faradayweg 4-6 e-mail: jacob at fhi-berlin.mpg.de
> > > D-14 195 Berlin-Dahlem Germany
> > > ----------------------------------------------------------------------
> > > WWW: http://www.fhi-berlin.mpg.de/th/th.html
> > >
> > > _______________________________________________
> > > Wien mailing list
> > > Wien at zeus.theochem.tuwien.ac.at
> > > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> >
> > -----------------------------------------------
> > Laurence Marks
> > Department of Materials Science and Engineering
> > MSE Rm 2036 Cook Hall
> > 2225 N Campus Drive
> > Northwestern University
> > Evanston, IL 60201, USA
> > Tel: (847) 491-3996 Fax: (847) 491-7820
> > mailto:L-marks at northwestern.edu
> > http://www.numis.northwestern.edu
> > -----------------------------------------------
> >
> > _______________________________________________
> > Wien mailing list
> > Wien at zeus.theochem.tuwien.ac.at
> > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>
> --
> Dr. Timo Jacob Phone : ++49-30-8413 4816
> Fritz-Haber-Institut Fax : ++49-30-8413 4701
> der Max-Planck-Gesellschaft
> Faradayweg 4-6 e-mail: jacob at fhi-berlin.mpg.de
> D-14 195 Berlin-Dahlem Germany
> ----------------------------------------------------------------------
> WWW: http://www.fhi-berlin.mpg.de/th/th.html
>
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>
-----------------------------------------------
Laurence Marks
Department of Materials Science and Engineering
MSE Rm 2036 Cook Hall
2225 N Campus Drive
Northwestern University
Evanston, IL 60201, USA
Tel: (847) 491-3996 Fax: (847) 491-7820
mailto:L-marks at northwestern.edu
http://www.numis.northwestern.edu
-----------------------------------------------
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