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[matthieu verstraete <matthieu.jean.verstraete@gmail.com>]

Ok, have you checked the ecut convergence exhaustively with SO? Probably not the issue, but it could be. Also, some of the HGH pseudopotentials have been known to give bad results, although it is a bit surprising.

toldfe 1.0d-7 is not very low - are you sure that everything is converging during the scf cycles and that the geometry relaxation is not running away (how low a pressure do you get)? You could try to do fixed-cell calculations for different lattice parameters, to see if the Broyden is the problem.

As always, please follow nettiquette fully (outputs log, architecture, version, etc)

Matthieu

On Thu, Mar 12, 2009 at 2:47 PM, Aldo Humberto Romero <aromero@qro.cinvestav.mx> wrote:

I agree with Matt, you should a problem on the pseudo... did you
look at the logout to see if the spin-orbit is properly
included? which pseudo did you use?

The other code you can use the include SO correction is the
Martin's code. You can follow the link in

http://www.abinit.org/Psps/?text=psps

Be sure that convergence is Ok, it is much expensive but
at least, our experience shows that usually, this correction improves
the results.. Hf is not the exception :-)


regards


-aldo.

> It probably is the pseudopotential. Where did you get the one with SO, if
> it's not an HGH?
>
> Matthieu
>
> On Thu, Mar 12, 2009 at 10:36 AM, <tomblister@hotmail.com> wrote:
>
>> Dear all,
>>  I'm doing the optimization calculation of Hf with spin-orbit coupling,
>> but
>> the
>> result crystal parameters deviate from the experiment wildly. without
>> considering the spin-orbit interaction, the results are way better. i
>> suppose
>> spin-orbit calculation with hgh pseudopotential would be more accurate,
>> so
>> what's the possible mistake in my calculation? following is my input
>> file
>> for
>> reference:
>>
>> ########################
>> #intxc 1
>> istwfk 1
>> nspinor 2
>> so_psp 2
>> #######################
>> #Definition of occupation numbers
>> occopt 6
>> tsmear 0.01
>> strprecon 0.001
>> #nsppol 2
>> #tphysel 0.0001
>> tolmxf  1.0d-6
>> #Definition of the unit cell
>> acell    5.8100225016E+00  5.8100225016E+00  9.1898541450E+00
>>
>> angdeg  90  90  120
>>
>> #Optimization of the lattice parameters
>> optcell 2
>> ionmov  2
>> ntime 100
>> dilatmx 2.0
>> ecutsm  0.5
>>
>> #Definition of the atom types
>> ntypat 1          # There is only one type of atom
>> znucl 72          # 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, the only type is
>> Iridium
>>
>> nband6 36
>> #Definition of the atoms
>> natom 2           # There is only one atom per cell
>> typat 1  1           # This atom is of type 1, that is, Iridium
>> xred              # This keyword indicate that the location of the atoms
>>                  # will follow, one triplet of number for each atom
>>   1/3  2/3  1/4
>>   2/3  1/3  3/4
>>
>> #Definition of the planewave basis set
>>
>> ecut 85
>>
>>
>> #Exchange-correlation functional
>> ixc 1             # LDA Teter Pade parametrization
>>
>> #Definition of the k-point grid
>>  #kptopt 1          # Option for the automatic generation of k points,
>> taking
>>                  # into account the symmetry
>>  ngkpt 12 12 8     # This is a 2x2x2 FCC grid, based on the primitive
>> vectors
>>  nshiftk 1
>>
>>
>>
>> shiftk   0.0 0.0 0.5
>>
>> #Definition of the SCF procedure
>> nstep 100          # Maximal number of SCF cycles
>> toldfe 1.0d-7    # Will stop when, twice in a row, the difference
>>                  # between two consecutive evaluations of total energy
>>                  # differ by less than toldfe (in Hartree)
>> #Print electronic density of states document
>> #prtdos 1
>>
>
>
>
> --
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Dr. Matthieu Verstraete
>
> European Theoretical Spectroscopy Facility (ETSF)
> Dpto. Fisica de Materiales,
> U. del Pais Vasco,
> Centro Joxe Mari Korta, Av. de Tolosa, 72,   Phone: +34-943018393
> E-20018 Donostia-San Sebastian, Spain        Fax  : +34-943018390
>
> Mail : matthieu.jean.verstraete@gmail.com
> http://www-users.york.ac.uk/~mjv500
>

---------------------------------------------------
Prof. Aldo Humberto Romero
CINVESTAV-Unidad Queretaro
Libramiento Norponiente 2000
CP 76230, Queretaro, QRO, Mexico
tel: 442 211 9909
fax: 442 211 9938
email: aromero@qro.cinvestav.mx
      aldorome@gmail.com
www: qro.cinvestav.mx/~aromero

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dr. Matthieu Verstraete

European Theoretical Spectroscopy Facility (ETSF) 
Dpto. Fisica de Materiales, 
U. del Pais Vasco,            
Centro Joxe Mari Korta, Av. de Tolosa, 72,   Phone: +34-943018393
E-20018 Donostia-San Sebastian, Spain        Fax  : +34-943018390

Mail : matthieu.jean.verstraete@gmail.com
http://www-users.york.ac.uk/~mjv500