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[hongkien <fenghongjian@ss.buaa.edu.cn>]

Dear Philippe,

Thanks for your kindly reply.I have already set nband=20,but failed. The
nband 12 could fix this problem, but the code stoped without giving any
error notice on the job as I relaxed the atomic position under the
finite electric field.The job stoped here:

ITER STEP NUMBER     4
 vtorho : nnsclo_now=  1, note that nnsclo,dbl_nnsclo,istep=  0 0  4

 Non-SCF iterations; k pt #    1  k=  0.08333  0.08333  0.08333  band
residuals:
 res:  5.03E-06  2.33E-05  2.19E-05  2.49E-05  1.13E-04  1.15E-04
4.29E-04  4.46E-04
 res:  1.34E-05  5.05E-04  2.07E-04  2.05E-04
 ene: -8.88E-01 -8.56E-01 -8.54E-01 -3.46E-01 -3.41E-01 -3.40E-01
-2.84E-01 -2.84E-01
 ene: -2.68E-01 -2.66E-01 -2.55E-01 -2.54E-01
 vtowfk : number of one-way 3D ffts skipped in vtowfk until now =
0
     eigenvalues (hartree) for   12  bands
              after    2 non-SCF iterations with    4 CG line
minimizations
 -8.8837E-01 -8.5567E-01 -8.5368E-01 -3.4636E-01 -3.4083E-01 -3.4028E-01
 -2.8401E-01 -2.8387E-01 -2.6847E-01 -2.6594E-01 -2.5472E-01 -2.5431E-01

 Non-SCF iterations; k pt #    2  k=  0.25000  0.08333  0.08333  band
residuals:
 res:  7.48E-06  2.02E-05  2.04E-05  1.21E-04  1.14E-04  1.18E-04
4.38E-04  4.05E-04
 res:  3.26E-04  2.95E-04  3.92E-04  2.35E-04
 ene: -8.81E-01 -8.56E-01 -8.53E-01 -3.65E-01 -3.45E-01 -3.42E-01
-3.06E-01 -3.05E-01
 ene: -2.84E-01 -2.74E-01 -2.65E-01 -2.62E-01
 vtowfk : number of one-way 3D ffts skipped in vtowfk until now =
0
     eigenvalues (hartree) for   12  bands
              after    2 non-SCF iterations with    4 CG line
minimizations
 -8.8061E-01 -8.5604E-01 -8.5337E-01 -3.6482E-01 -3.4468E-01 -3.4171E-01
 -3.0639E-01 -3.0513E-01 -2.8351E-01 -2.7449E-01 -2.6483E-01 -2.6222E-01

 Non-SCF iterations; k pt #    3  k=  0.41667  0.08333  0.08333  band
residuals:
 res:  2.21E-05  1.61E-05  1.91E-05  8.21E-05  1.25E-04  1.00E-04
3.02E-04  3.54E-04
 res:  2.64E-04  3.72E-04  4.17E-04  2.11E-04
 ene: -8.70E-01 -8.59E-01 -8.53E-01 -3.82E-01 -3.46E-01 -3.44E-01
-3.28E-01 -3.18E-01
 ene: -2.88E-01 -2.84E-01 -2.75E-01 -2.69E-01
 vtowfk : number of one-way 3D ffts skipped in vtowfk until now =
0
     eigenvalues (hartree) for   12  bands
              after    2 non-SCF iterations with    4 CG line
minimizations
 -8.6987E-01 -8.5929E-01 -8.5321E-01 -3.8242E-01 -3.4649E-01 -3.4395E-01
 -3.2765E-01 -3.1819E-01 -2.8754E-01 -2.8393E-01 -2.7486E-01 -2.6871E-01

 Non-SCF iterations; k pt #    4  k=  0.25000  0.25000  0.08333  band
residuals:
 res:  4.47E-06  1.86E-05  1.79E-05  1.24E-04  8.31E-05  2.11E-04
2.93E-04  4.04E-04
 res:  4.18E-04  3.29E-04  9.57E-05  1.00E-04
 ene: -8.75E-01 -8.55E-01 -8.55E-01 -3.73E-01 -3.55E-01 -3.43E-01
-3.35E-01 -3.11E-01
 ene: -2.98E-01 -2.74E-01 -2.68E-01 -2.57E-01
 vtowfk : number of one-way 3D ffts skipped in vtowfk until now =
0
     eigenvalues (hartree) for   12  bands
              after    2 non-SCF iterations with    4 CG line
minimizations
 -8.7470E-01 -8.5546E-01 -8.5460E-01 -3.7317E-01 -3.5481E-01 -3.4328E-01
 -3.3465E-01 -3.1117E-01 -2.9771E-01 -2.7428E-01 -2.6828E-01 -2.5653E-01

 Non-SCF iterations; k pt #    5  k=  0.41667  0.25000  0.08333  band
residuals:
 res:  1.72E-05  1.33E-05  1.81E-05  1.02E-04  1.57E-04  1.69E-04
1.95E-04  2.89E-04
 res:  4.92E-04  2.94E-04  1.49E-04  2.45E-04
 ene: -8.67E-01 -8.57E-01 -8.55E-01 -3.86E-01 -3.61E-01 -3.56E-01
-3.42E-01 -3.23E-01
 ene: -2.98E-01 -2.81E-01 -2.73E-01 -2.53E-01
 vtowfk : number of one-way 3D ffts skipped in vtowfk until now =
0
     eigenvalues (hartree) for   12  bands
              after    2 non-SCF iterations with    4 CG line
minimizations
 -8.6694E-01 -8.5744E-01 -8.5518E-01 -3.8583E-01 -3.6118E-01 -3.5604E-01
 -3.4178E-01 -3.2267E-01 -2.9768E-01 -2.8078E-01 -2.7301E-01 -2.5340E-01

 Non-SCF iterations; k pt #    6  k=  0.41667  0.41667  0.08333  band
residuals:



It will be highly appreciated for pointing the error.Thank you.

My input file reads:

# : computation of the response to homogeneous
# electric field and atomic displacements, at q=0
#

  ndtset  3

#Ground state calculation
  kptopt1   1             # Automatic generation of k points, taking
                          # into account the symmetry
  tolvrs1   1.0d-18       # SCF stopping criterion
    iscf1   5             # Self-consistent calculation, using algorithm
5

#Response Function calculation : d/dk
  rfelfd2   2             # Activate the calculation of the d/dk
perturbation
   rfdir2   0 0 1         # Need to consider the perturbation in the
x-direction only
                          # This is rather specific, due to the high
symmetry of the AlAs crystal
                          # In general, just use rfdir 1 1 1
                          # In the present version of ABINIT (v4.6),
symmetry cannot be used
                          # to reduce the number of ddk perturbations

    nqpt2   1
     qpt2   0.0 0.0 0.0   # This is a calculation at the Gamma point

  getwfk2   -1            # Uses as input the output wf of the previous
dataset

  kptopt2   2             # Automatic generation of k points,
                          # using only the time-reversal symmetry to
decrease
                          # the size of the k point set.

    iscf2  -3             # The d/dk perturbation must be treated 
                          # in a non-self-consistent way
  tolwfr2   1.0d-22       # Must use tolwfr for non-self-consistent
calculations
                          # Here, the value of tolwfr is very low.

#Response Function calculation : electric field perturbation and phonons
  rfphon3   1             # Activate the calculation of the atomic
dispacement perturbations
 rfatpol3   1 2 3           # All the atoms will be displaced
  rfelfd3   3             # Activate the calculation of the electric
field perturbation
   rfdir3   0  0 1         # All directions are selected. However,
symmetries will be used to decrease
                          # the number of perturbations, so only the x
electric field is needed
                          # (and this explains why in the second
dataset, rfdir was set to 1 0 0).

    nqpt3   1
     qpt3   0.0 0.0 0.0   # This is a calculation at the Gamma point

  getwfk3   -2            # Uses as input wfs the output wfs of the
dataset 1
  getddk3   -1            # Uses as input ddk wfs the output of the
dataset 2

  kptopt3   2             # Automatic generation of k points,
                          # using only the time-reversal symmetry to
decrease
                          # the size of the k point set.
  tolvrs3   1.0d-8
    iscf3   5             # Self-consistent calculation, using algorithm
5


#######################################################################
#Common input variables

#Definition of the unit cell
   acell 3*7.6153
   rprim 
1     0     0
0      1      0
0     0      1.01319
#Definition of the atom types
#ntypat 2               # There are two types of atom
#znucl 13 33            # The keyword "znucl" refers to the atomic
number of the 
                       # possible type(s) of atom. The
pseudopotential(s) 
                       # mentioned in the "files" file must correspond
                       # to the type(s) of atom. Here, type 1 is the
Aluminum,
                       # type 2 is the Arsenic.

#Definition of the atoms
   natom 5
   ntypat 3
   znucl 56  22  8
   typat 1 2 3  3  3
   xred 
0.00000     0.00000     0.00000
0.50000   0.50000   0.50000
0.50000   0.50000   0.00000
0.00000     0.50000   0.50000
0.50000   0.00000     0.50000

#Gives the number of band, explicitely (do not take the default)
nband  12              # For an insulator (if described correctly as an
insulator 
                       # by DFT), there is no need to include conduction
bands 
                       # in response-function calculations

#Exchange-correlation functional
ixc 1             # LDA Teter Pade parametrization

#Definition of the planewave basis set
 ecut    20.0           # Maximal kinetic energy cut-off, in Hartree

#Definition of the k-point grid
   kptopt 1
   ngkpt 6 6 6
   nshiftk 1
   shiftk 0.5 0.5 0.5


#Definition of the SCF procedure
nstep 15               # Maximal number of SCF cycles
diemac 9.0             # Although this is not mandatory, it is worth to
                       # precondition the SCF cycle. The model
dielectric
                       # function used as the standard preconditioner
                       # is described in the "dielng" input variable
section.
                       # The dielectric constant of AlAs is smaller that
the one of Si (=12).


Best regards,
Hongkien Feng

Physics department
Beijing University of 
aeronautics & astronautics

在 2007-08-30四的 17:07 +0200，Philippe Ghosez写道：
> Dear Hongkien,
> 
> you should probably specify the number of bands explicitely
> in the input (it seems it is not in your file) .
> 
> If you treat semicore states, I think it should be  nband = 20
> (40 valence electrons: 10 electrons from Ba 5s,5p,6s
> + 12 electrons from Ti 3s,3p,3d,4s + 3x6 electrons from O 2s,2p)
> 
> Cheers,
> 
> Philippe.
> 
> 
> On 30 Aug 2007, at 21:03, hongkien wrote:
> 
> > Dear abinit users,
> >
> >     I have been calculating the ferroelctric properties of BaTiO3 using
> > the finite electric field method.For zero field, the code could give 
> > the
> > polarization of berry phase. unfortunately, the code produced the error
> > as the electric field was turned on:
> >
> > initberry: ERROR -
> >   In a finite electric field calculation, nband must be equal
> >   to the number of valence bands.
> >
> >  leave_new : decision taken to exit ...
> >
> > The nband was given varing from 22 to 13, but still could not give the
> > right number of valence bands. From the experience in using PWSCF, the
> > number of valence bands should be half of total valence electrons in 
> > the
> > cell, then it should be 22. And as we know, BaTiO3 was a classic
> > insulator avoiding the metal collpase in berry phase calculation.I am
> > frustrated by this problem, any suggestion will be highly
> > appreciated.Thank you in advance.
> >
> > My input file was pasted here:
> > # Finite electric field calculation of alas at clamped atomic positions
> > # (M. Veithen, 04.5.2005)
> >
> > #Definition de la maille elementaire
> > #**********************************
> >    acell 3*7.6153
> >    rprim
> > 1     0     0
> > 0      1      0
> > 0     0      1.01319
> >
> > #Definition des atomes
> > #*********************
> >    natom 5
> >    ntypat 3
> >    znucl 56  22  8
> >    typat 1 2 3  3  3
> >    xred
> > 0.00000     0.00000     0.00000
> > 0.50000   0.50000   0.50000
> > 0.50000   0.50000   0.00000
> > 0.00000     0.50000   0.50000
> > 0.50000   0.00000     0.50000
> > #Definition de la procedure scf
> > #******************************
> >    iscf 5
> >    nstep 15
> >
> > #Definition de la base d'ondes planes
> > #************************************
> >    ecut  20
> >    ecutsm 0.5
> >    kptopt 1
> >    ngkpt 6 6 6
> >    nshiftk 1
> >    shiftk 0.5 0.5 0.5
> >
> >    toldfe 1.0d-12
> >
> >
> > ndtset  11
> >  # ndtset   2
> > jdtset  11
> >  21 22 23  24  25     # The additional 8 values of the field have been
> > suppressed to spare CPU time
> >      31   32  33  34  35
> >
> > berryopt11 -1       rfdir11    0  0  1
> >
> > berryopt21  4       efield21   0.000  0.000  0.001    getwfk21  11
> > berryopt22  4       efield22   0.000  0.000  0.002    getwfk22  21
> > berryopt23  4       efield23   0.000  0.000  0.003    getwfk23  22
> > berryopt24  4       efield24   0.000  0.000  0.004    getwfk24  23
> > berryopt25  4       efield25   0.000  0.000  0.005    getwfk25  24
> >
> > berryopt31  4       efield31  -0.000 -0.000 -0.001    getwfk31  11
> > berryopt32  4       efield32  -0.000 -0.000 -0.002    getwfk32  31
> > berryopt33  4       efield33  -0.000 -0.000 -0.003    getwfk33  32
> > berryopt34  4       efield34  -0.000 -0.000 -0.004    getwfk34  33
> > berryopt35  4       efield35  -0.000 -0.000 -0.005    getwfk35  34
> >
> >
> > nbdbuf 0
> >
> >
> >
> >  Best regards,
> >
> > Hongkien Feng
> >
> > Physics department
> > Beijing University of
> > aeronautics&astronautics
> >
> >
> >
> --------------------------------------------------
> Philippe GHOSEZ
> Universite de Liege
> Institut de Physique, Bat. B5
> Allee du 6 aout, 17
> B- 4000 Sart Tilman
> BELGIUM
> 
> Phone : ++(32) (0)4-366.36.11
> Fax   : ++(32) (0)4-366.36.29
> E-mail: Philippe.Ghosez@ulg.ac.be
> 
> http://www.ulg.ac.be/phythema
> --------------------------------------------------
>