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[david.hendry@mandmd.com.au]

Dear Abinitians,

I'm trying to relax a single unit cell of CaTiO3 with two Ca removed and one 
Sm added.  The geometry does not converge fast enough: after 200 nsteps the 
potential residual is still above 1.  Each ntime step therefore only 
marginaly reduces the atomic forces.  The input file is added below.  I'm 
using Troullier-Martins norm-conserving psps.  Might there be some way to 
allow this to work more efficiently?

Regards,

David.

 
#Definition of lattice parameters
#********************************
  acell  10.1629 14.4451 10.2329

#Definition of atomic positions and types
#****************************************
   natom       19
   ntypat      4
   znucl       22 20 62 8
   typat       1 1 1 1 2 3 3 4 4 4 4 4 4 4 4 4 4 4 4
   xred        0      0     0.5
               0.5    0     0
               0      0.5   0.5
               0.5    0.5   0
               0.9937 0.25  0.03339
               0.5063 0.75  0.53339
               0.4937 0.25  0.46661
               0.0707 0.25  0.4842
               0.4293 0.75  0.9842
               0.9293 0.75  0.5158
               0.5707 0.25  0.0158
               0.711  0.037 0.2884
               0.789  0.963 0.7884
               0.289  0.537 0.7116
               0.211  0.463 0.2116
               0.289  0.963 0.7116
               0.211  0.037 0.2116
               0.711  0.463 0.2884
               0.789  0.537 0.7884



#Echange-correlation functional
#******************************
   ixc         1

#Plane wave basis and k-point grid
#*********************************
   #pawecutdg   60
   ecut        42
   ngkpt       7 5 7
   nshiftk     1
   shiftk      0.5 0.5 0.5
   nband       53
   ngfft       60  90  60

#Relax ions and unit cell
#************************
    #chkprim    0
    kptopt     1
    iscf       7
    pulayit    20
    tolvrs     1.0d-18
    tolmxf     1.0d-8
    nstep      200
    optcell    0
    ionmov     3
    ntime      200
    dilatmx    1.1
    ecutsm     0.5
    prtwf      0
    prtden     0