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["Cote Michel" <michel.cote@umontreal.ca>]

Try iscf = 5 (the default option) . Option 3 can be quite slow.

I hope it helps.

Michel

-- 
***************************************************************
  Michel Cote                          tel: +1 (514) 343-5628
  Professeur adjoint                   fax: +1 (514) 343-2071
  Département de physique
  Université de Montréal
  C.P. 6128, succ. Centre-ville
  Montréal (Québec) H3C 3J7          Michel.Cote@umontreal.ca
  Canada                   www.phys.umontreal.ca/~michel_cote
***************************************************************
Le 12/07/05 10:32, « silvia@cii.fc.ul.pt » <silvia@cii.fc.ul.pt> a écrit :

> Dear ABINIT users,
> 
> I'm trying to optimize one phenol molecule using the Perdew-Burke-Ernzerhof
> GGA functional (ixc=11) and Fritz-Haber-Institute (FHI) pseudopotentials
> within the GGA aproximation.
> I'm considering a unit cell with dimensions 20.0 20.0 20.0. I'm using the 
> data
> set mode to vary the value of ecut while maintaining the cell dimensions
> fixed. The problem is that I'm not getting convergence on the force 
> gradients
> during the Broyden minimization (ionmov=3). I've used 35.0 and 40.0 hartree 
> as
> ecut values and 100 optimization steps (ntime=100). I'm not achieving
> convergence on the SCF cycles either.
> 
> This is the input file I'm using:
> 
> ndtset 4
> acell 20.0 20.0 20.0
> ecut: 35.0 ecut+ 5
> 
> ntypat 3         
> znucl 8 6 1      
> 
> natom 13
> typat 1 1 1 1 1 1 2 2 2 2 2 3 2
> 
> xangst
> 
>             0.939974   -0.024981    0.000001
>             0.221909   -1.222557    0.000001
>            -1.169193   -1.188258    0.000000
>            -1.854307    0.027925   -0.000001
>            -1.128953    1.217603    0.000000
>             0.265046    1.197679    0.000000
>             0.767230   -2.166033    0.000004
>            -1.725398   -2.126674    0.000001
>            -2.943885    0.047328    0.000000
>            -1.649437    2.176230   -0.000001
>             0.828963    2.133524   -0.000001
>             2.300265   -0.110628   -0.000003
>             2.673550    0.776176    0.000014
> 
> ixc  11
> 
> nkpt 1
> ntime 100
> ionmov 3
> tolmxf 5.0d-5
> 
> iscf 3            # Algorithm for SCF
> nstep 50          # Maximal number of SCF cycles
> toldff 5.0d-6
> diemac 1.0       
> diemix 0.5       
> 
>                  
> Can someone give me some clue on what I'm doing wrong or not doing at all?
> Any help would be greatly appreciated...
> 
> Best regards,
> Sílvia Estácio
> 
> 
> 
>