The ABINIT Users Mailing List ( CLOSED )

[Xenophon Krokidis <Xenophon.Krokidis@scienomics.com>]

Dear All,

my calculation of elastic constants converges with no problem however I 
get the following WARNING (see below) and I can't figure out what could 
be the problem. My input file is attached.

 WARNING : Localization tensor in reciprocal space incomplete,
           transformation to cartesian coordinates may be wrong.

Thank you in advance for the help.

Best regards,

Xenophon



D. R. Hamann wrote:
> Dear Xenophon,
>
> Your shiftk,  copied and pasted from your input  file is
> shiftk 0.5 0.5 0.5
> I assume you just attached the wrong input file, since  the  output 
> file you attached had 0 0 0 at the start of each set of kpoints.
>
> I believe the  problem is
> ngkpt 6 6 5
> This will certainly break trigonal symmetry for your k set.
>
> Best regards,
> Don Hamann
>
>
> Xenophon Krokidis wrote:
> > Dear Xavier,
> >
> > thank you for you answer which solved partly my problem. I simply 
> > increased the k-point grid. However, now I get an other error message 
> > and ABINIT stops. This is related to the shiftk I use.
> >
> > In the input file attached here you see that I have a shiftk of 0.0 
> > 0.0 0.0, and the right kptopt but still ABINIT stops with message :
> >
> >  symkchk : ERROR -
> >    k-point set must have full space-group symmetry
> >    there is no match for kpt   2 transformed by symmetry   5
> >    Action : change kptopt to 2 or 3 and/or change or use shiftk
> >             shiftk = 0 0 0 is always a safe choice.
> >
> > Any help on this problem is very much appreciated as well as what 
> > should be the right shiftk for rhombohedral systems.
> >
> > Best regards,
> >
> > Xenophon
> >
> > PS. I am attaching also the output file.
> >
> >
> >
> >
> > Xavier Gonze wrote:
> > > Seems that you did not ask ABINIT to compute all perturbations
> > > (and to decide by itself which ones were not needed owing to symmetry).
> > > At least you should mention
> > >
> > > rfdir 1 1 1
> > >
> > > But rfatpol might have to be changed. Difficult to say more without 
> > > input file...
> > > X.
> > >
> > > On 14 Nov 2009, at 01:45, Xenophon Krokidis wrote:
> > >
> > > > Dear All,
> > > >
> > > > in a calculation of elastic properties I got the following warnings :
> > > >
> > > > WARNING : still subject to testing - especially symmetries.
> > > >
> > > > WARNING : Localization tensor in reciprocal space incomplete,
> > > >         transformation to cartesian coordinates may be wrong.
> > > >
> > > > chkph3 : WARNING -
> > > > The dynamical matrix was incomplete : phonon frequencies may be 
> > > > wrong ...
> > > >
> > > > Does anyone know what is going wrong ?
> > > >
> > > > Regards,
> > > >
> > > > Xenophon
> > > >
> > > > <Xenophon_Krokidis.vcf>
# corundum
#AlAs in hypothetical wurzite (hexagonal) structure
#Response function calculation for:
#    * rigid-atom elastic tensor
#    * rigid-atom piezoelectric tensor
#    * interatomic force constants at gamma
#    * Born effective charges

   ndtset   3

# Set 1 : Initial self-consistent run

    iscf1   5
  kptopt1   1
  tolvrs1   1.0d-20  #need excellent convergence of GS quantities for RF runs


# Set 2 : Calculate the ddk wf's - needed for piezoelectric tensor and
#         Born effective charges in dataset 3

  getwfk2  -1
    iscf2  -3        #this option is needed for ddk
  kptopt2   2        #use time-reversal symmetry only for k points
    nqpt2   1        #one wave vector will be specified
     qpt2   0 0 0    #need to specify gamma point
  rfelfd2   2        #set for ddk wf's only
   rfdir2   1 1 1    #full set of directions needed
  tolwfr2   1.0d-20  #only wf convergence can be monitored here

# Set 3 : response-function calculations for all needed perturbations

  getddk3  -1
  getwfk3  -2
    iscf3   5
  kptopt3   2        #use time-reversal symmetry only for k points
    nqpt3   1
     qpt3   0 0 0
  rfphon3   1        #do atomic displacement perturbation
 rfatpol3   1 10     #do for all atoms
  rfstrs3   3        #do strain perturbation
   rfdir3   1 1 1    #the full set of directions is needed
  tolvrs3   1.0d-12  #need reasonable convergence of 1st-order quantities

 acell    9.7948988941E+00  9.7948988941E+00  9.7948988941E+00 Bohr
 angdeg  55.30430993  55.30430993  55.30430993
#angdeg 55.28 55.28 55.28
 chkprim 0
 ecut 1700 eV
 kptopt 1
 ngkpt 8 8 8
 nshiftk 1
 shiftk 0.0 0.0 0.0
 nstep 100
 ixc 11
 nband  24
 nsppol 1
 natom 10
#nsym 1
#symrel 1 0 0  0 1 0  0 0 1
 ntypat 2
 occopt 1
 ecutsm 0.5
 typat 1 2 2 2 1 1 2 2 2 1
      xred    3.5240258377E-01  3.5240258377E-01  3.5240258377E-01
              5.5623592596E-01  9.4376407404E-01  2.5000000000E-01
              2.5000000000E-01  5.5623592596E-01  9.4376407404E-01
              9.4376407404E-01  2.5000000000E-01  5.5623592596E-01
              1.4759741623E-01  1.4759741623E-01  1.4759741623E-01
              6.4759741623E-01  6.4759741623E-01  6.4759741623E-01
              4.4376407404E-01  5.6235925957E-02  7.5000000000E-01
              7.5000000000E-01  4.4376407404E-01  5.6235925957E-02
              5.6235925957E-02  7.5000000000E-01  4.4376407404E-01
              8.5240258377E-01  8.5240258377E-01  8.5240258377E-01
     znucl     13.00000    8.00000

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