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[ghada ameereh <ghaddosh@yahoo.com>]

Dear Sir
 i study the compounds of FeSi after replacing Si atom
by Ge atom ;i.e. Fe4Si3Ge ,Fe4Si2Ge ...etc but FeSi is
semiconductur butwhen Ge atoms increased ;the energy
gap is decreased and the metallic properties are
increased ...so i don't know how to regard these
compound (metallic or seamiconductor)..
  thanks for reading my message.
    ghada

--- Masayoshi Mikami <mmikami@rc.m-kagaku.co.jp>
wrote:

> Dear Ghada,
> 
> I do not know what your system is like,
> but I guess that you may have many possibilities:
> 
> - increase dilatmx, but it may be tested last,
> before that ...
> - please be aware that your system is metallic.
>    So that occopt needs to be set  3 ... 7. (the
> default is 1 !)
>    You will need set tsmear as well. Please try our
> Tutorials/Test*
>    in the tar.gz package to learn the details.
>    In passing, diemac may be set to the default.
> - nstep (10) may be much more increased ...
>    you might notice some warnings about SCF
> convergence ?
> - "toldfe 1.0d-6" may not be good. Try other tol*
> parameter,
>    e.g. tolvrs (1.0d-12 - 1.0d-10 ?)
> - Your pseudopotential may be still improved ?
> (Which one)
>    please be aware that ecut may depend on your
> pseudos.
> - ... (or something else ?) If your system is just a
> model,
>    the initial guess for the geometry may be far
> from
>    a (possible) plausible structure ...
> 
> In any case, you might want to try the
> Tutorial/Test*.
> Such a "detour" (you might think so ?) may be a
> shortcut
> to your goal...
> 
> In passing, you might want to have more appropriate
> subject, if you could take a look at our netiquette:
> http://www.abinit.org/community/?text=netiquette
> 
> Good luck,
> Masayoshi (now in Yokohama... ;-)
> 
> On 2005/09/05, at 1:46, ghada ameereh wrote:
> 
> > Dear sir :
> > i attend to make convergence tests but i faced a
> > problem.
> > input file:
> >
> > #Fe4Si3Ge Crystal :
> >
> > strprecon 0.1
> > ionmov 3
> > ntime 10
> > dilatmx 1.1
> > ecutsm 0.5
> > optcell 1
> >
> >
> > kptopt 1
> > nshiftk 1
> > shiftk 0.5 0.5 0.5
> >
> >
> >
> >
> > ngkpt 6 6 6
> >
> > rprim 1 0 0
> >       0 1 0
> >       0 0 1
> >
> > acell 3*9.5
> >
> > ixc 1
> > ntypat 3
> > znucl 26 14 32
> > natom 8
> > typat 1 1 1 1 2 2 2 3
> > xred  0.3525 0.3525 0.3525
> >     -0.3525 0.8525 0.1475
> >      0.1475 -0.3525 0.8525
> >      0.8525 0.1475 -0.3525
> >     -0.3525 -0.3525 -0.3525
> >      0.3525 0.1475 0.8525
> >      0.8525 0.3525 0.1475
> >      0.1475 0.8525 0.3525
> >
> > ecut 30
> > nstep 10
> > toldfe 1.0d-6
> > diemac 12.0
> >
> >
> > The log file give me: chkdilatmx: ERROR -
> >   The new primitive vectors rprimd (an evolving
> > quantity)
> >   are too large with respect to the old rprimd and
> the
> > accompanying dilatmx :
> >   this large change of unit cell parameters is not
> > allowed by the present value of dilatmx.
> >   You need at least dilatmx=    1.281035E+00
> >   Action : increase the input variable dilatmx.
> >
> >  leave_new : decision taken to exit ...
> > FORTRAN STOP  1
> >
> > i will appreciate your advice.
> >
> > --- verstraete@pcpm.ucl.ac.be wrote:
> >
> >>
> >> Your dilatmx is huge. Go see the definition and
> use
> >> <= 1.1
> >>
> >>
> http://www.abinit.org/Infos_v4.6/varrlx.html#dilatmx
> >>
> >> For the rest, send your output/log etc... please
> >> read the netiquette
> >>
> >> http://www.abinit.org/community/?text=netiquette
> >>
> >> Matthieu
> >
> 
> 


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