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

Hello Wei Cheng,

if you just want the band structure, you would be better off with a
single unit cell. The 16 atoms is a huge waste

The SO coupling will be included if it is present in the
pseudopotential file. Nspinor 2 just forces abinit to use spinorial
wavefunctions.

Your calculation would be more precise with a shifted grid in DS1 -
any reason to keep it centered?

And finally, you should be very careful with the band structure points
you use: your cell is not primitive, so all the bands will be folded,
and further you should check that your (reduced coordinate) kpoints
are really the high-symmetry points you are looking for (I can't tell
off the top of my head). You need to verify that they are in
conventional cubic coordinates (not wrt primitive translations as is
often the case) and that they are scaled correctly for the band
folding.

Matthieu

On Mon, Apr 20, 2009 at 7:38 PM, wei cheng <chengwei0@hotmail.com> wrote:
> Hi,
> I tried to calculate the band structures for 16 Ge atom supercell.
> I want to include spin-orbit coupling effect.
> Please see the following.
> Is the input correct?
>
> ndtset 2
> nspinor 2
> nband 96
>
> kptopt1 1          # Option for the automatic generation of k points,
> nshiftk1 1
> shiftk1  0.0 0.0 0.0  # These shifts will be the same for all grids
> ngkpt1  8 8 4
> prtden1  1         # Print the density, for use by dataset 2
> toldfe1  1.0d-6
>
> iscf2    -2
> getden2  -1
> kptopt2  -3
> ndivk2   52 60 42      # 10, 12 and 17 divisions of the 3 segments,
> delimited
> kptbounds2  0.5  0.5  0.25 # L point
>             0.0  0.0  0.0 # Gamma point
>             0.5  0.0  0.0 # X point
>             0.5  0.5  0.5 # Gamma point in another cell.
> tolwfr2  1.0d-12
> enunit2  1             # Will output the eigenenergies in eV
> #Definition of the unit cell
> acell  2*10.906645960 21.813291920
> rprim  1.0  0.0  0.0
>        0.0  1.0  0.0   # (to be scaled by acell) were 1 0 0  0 1 0  0 0 1
>        0.0  0.0  1.0   # that is, the default.
>
> natom 16
> ntypat 1
> znucl 32
> typat 1 1 1 1  1 1 1 1  1 1 1 1  1 1 1 1
> xred              # This keyword indicate that the location of the atoms
>    0.0  0.0  0.0  # Triplet giving the REDUCED coordinate of atom 1.
>    1/2  0.0  1/4
>    0.0  1/2  1/4
>    1/2  1/2  0.0
>    1/4  1/4  1/8
>    3/4  1/4  3/8
>    1/4  3/4  3/8
>    3/4  3/4  1/8
>    0.0  0.0  1/2
>    1/2  0.0  3/4
>    0.0  1/2  3/4
>    1/2  1/2  1/2
>    1/4  1/4  5/8
>    3/4  1/4  7/8
>    1/4  3/4  7/8
>    3/4  3/4  5/8
>
> ecut 15.0         # Maximal kinetic energy cut-off, in Hartree
> nstep 100          # Maximal number of SCF cycles
> diemac 16.0       # Although this is not mandatory, it is worth to
> chkprim 0
>
>
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-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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