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

Moreover are you sure your ecut is converged enough. I have at least
two examples of relaxations where a ecut giving Error(ETOT) < 1e-3
Hartree would not be enough to perform correctly a relaxation.

On Tue, Mar 10, 2009 at 4:34 PM,  <6671011@163.com> wrote:
> Dear Emmanuel,
>
> Though it speeds up the calculation a lot, I will not "perform an internal
> relaxation before relaxing the box". According to my experiences in Carbon
> Nanotubes, sometimes they do give the same results---which could be a 
> disaster
> if one cares about the energy.
>
> Sincerely,
> Guangfu Luo
>
>
>
> ----------------------------------------------------------------------------------------------------
>
> What about warnings?
> You use occopt 3 but you don't specify nband. Are you sure that makes no
> problem? Is it a metal? An insulator?
> toldfe e-6 is a bit low... e-8 should be better.
> Maybe you should perform an internal relaxation before relaxing the box.
>
> Emmanuel ARRAS
>
>
> ---------------------------------------------------------------------------------------------------
>
> dsagfds a écrit :
>
> Dear abinit users,
>
> I am trying to calculate the optimized acell of Phase-change material
> Ge1Sb2Te4,which is widely used in the optical storage apeplication.The
> supercell in the calculation is formed by 8*Ge1Sb2Te4.I am sure there is
> nothing wrong with my model, so there must be something wrong in other
> parameters.When I run the relaxation, I found strong discontinuities in 
> acell,
> #####################################################
> acell= 2.2000000000E+01 2.2000000000E+01 2.2000000000E+01
> acell= 2.2000000000E+01 2.2000000000E+01 2.2000000000E+01
> acell= 2.2218736471E+01 2.2215964594E+01 2.2218447042E+01
> acell= 2.2218736471E+01 2.2215964594E+01 2.2218447042E+01
> acell= 2.5092656679E+01 2.5051982098E+01 2.5086577317E+01
> acell= 2.5092656679E+01 2.5051982098E+01 2.5086577317E+01
> acell= 2.3329634141E+01 2.3311234526E+01 2.3327636658E+01
> ######################################################
> After a day long's calculation, the computation stoped eventually with
> following indication
>
> scfcge : ERROR -
> Potential-based CG line minimization not converged after 13 restarts.
> Action : read the eventual warnings about lack of convergence.
>
> You will find in the present mail my input and also the results of the
> calculations.
> Is my input wrong ? Thanks a lot to help me if someone has a good idea.
>
> Sincerely yours,
> dsagfds
>
>
> Here is my input file
> #Definition of the unit cell
> acell 3*22.0000000000 rprim 1.000000000000 0.000000000000 0.000000000000
> 0.000000000000 1.000000000000 0.000000000000
> 0.000000000000 0.000000000000 1.000000000000
> #definition of relaxation
> optcell 2
> ionmov 3
> ntime 40
> dilatmx 1.4
> ecutsm 0.6
> ortalg 2
> prtcml 1
> prtvol 10
>
> #definition of k grids
> kptopt 1
> ngkpt 2 2 2
>
> #definition of atoms
> ntypat 3 znucl 51 32 52 natom 56 typat 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 
> 3 3
> 3 3 3 3 3 3 3 3 3 3 3 3 1 2 1 2 1
> 1 2 1 1 1 2 1 2 1 1 2 1 1 1 2 1 1 1 2 xred 0.500000000000 0.000000000000
> 0.000000000000 0.750000000000 0.250000000000 0.000000000000 0.750000000000
> 0.000000000000 0.250000000000 0.000000000000 0.000000000000 0.000000000000
> 0.250000000000 0.250000000000 0.000000000000 0.500000000000 0.500000000000
> 0.000000000000 0.750000000000 0.750000000000 0.000000000000 0.250000000000
> 0.000000000000 0.250000000000 0.500000000000 0.250000000000 0.250000000000
> 0.750000000000 0.500000000000 0.250000000000 0.500000000000 0.000000000000
> 0.500000000000 0.750000000000 0.250000000000 0.500000000000 0.750000000000
> 0.000000000000 0.750000000000 0.000000000000 0.500000000000 0.000000000000
> 0.250000000000 0.750000000000 0.000000000000 0.000000000000 0.250000000000
> 0.250000000000 0.250000000000 0.500000000000 0.250000000000 0.500000000000
> 0.750000000000 0.250000000000 0.000000000000 0.000000000000 0.500000000000
> 0.250000000000 0.250000000000 0.500000000000 0.500000000000 0.500000000000
> 0.500000000000 0.750000000000 0.750000000000 0.500000000000 0.250000000000
> 0.000000000000 0.750000000000 0.500000000000 0.250000000000 0.750000000000
> 0.750000000000 0.500000000000 0.750000000000 0.000000000000 0.750000000000
> 0.250000000000 0.000000000000 0.500000000000 0.500000000000 0.250000000000
> 0.750000000000 0.500000000000 0.000000000000 0.250000000000 0.750000000000
> 0.250000000000 0.500000000000 0.750000000000 0.500000000000 0.750000000000
> 0.750000000000 0.000000000000 0.750000000000 0.750000000000 1.000000000000
> 0.500000000000 0.250000000000 1.000000000000 0.250000000000 0.500000000000
> 0.250000000000 0.250000000000 0.250000000000 0.500000000000 0.500000000000
> 0.250000000000 0.750000000000 0.750000000000 0.250000000000 1.000000000000
> 1.000000000000 0.250000000000 0.500000000000 0.250000000000 0.500000000000
> 1.000000000000 0.750000000000 0.500000000000 0.750000000000 0.250000000000
> 0.750000000000 1.000000000000 0.250000000000 1.000000000000 0.250000000000
> 0.750000000000 0.250000000000 0.500000000000 1.000000000000 0.250000000000
> 0.250000000000 0.500000000000 0.500000000000 0.750000000000 1.000000000000
> 0.500000000000 0.250000000000 0.250000000000 0.750000000000 0.750000000000
> 0.750000000000 0.750000000000 1.000000000000 1.000000000000 0.750000000000
> 0.500000000000 0.250000000000 1.000000000000 1.000000000000 0.750000000000
> 1.000000000000 0.250000000000 1.000000000000 0.500000000000 0.250000000000
> 0.750000000000 0.750000000000 0.250000000000 0.500000000000 1.000000000000
> 0.500000000000 0.750000000000 1.000000000000 0.750000000000 1.000000000000
> 1.000000000000
> # definiton of scf process
> iscf 5
> nstep 80
> diemac 500
> occopt 3
> enunit 2 tsmear 0.04 ecut 10 toldfe 1.0d-6
>
>



-- 
Pierre-Matthieu Anglade