The ABINIT Users Mailing List ( CLOSED )

[Emmanuel Arras <emmanuel.arras@cea.fr>]

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 
>
>