[Wannier] What is correct usage of translate_home_cell and translation_centre_frac?

[Mostofi, Arash]

Dear Wannier90 user,

One of the conventions for the use of this mailing list is to sign with your name and affiliation in all posts, and we would all be very grateful if you would please adhere to this convention.

I think translate_home_cell is working as expected: those centres reported in the .xyz file (in Cartesian coordinates in Angstrom) do seem to be in the home cell (ie, if you convert the coordinates to fractional coordinates of the real-space lattice, the coefficients will be in the range 0 to 1).

Best wishes,

Arash

—
Arash Mostofi — www.mostofigroup.org<http://www.mostofigroup.org>
Director, CDT in Theory and Simulation of Materials
Director, Thomas Young Centre @Imperial
Imperial College London

On 1 May 2017, at 16:32, balabi <balabi at qq.com<mailto:balabi at qq.com>> wrote:

Hi, everyone. I am trying to use translate_home_cell in order to make all wannier centers located inside home unit cell. But I found it is not working as I expected it to be.

I am using wannier90-2.1.0. Take example05 diamond as an example. If I change the projection to below

f=0.39665,0.39200,0.66574:s
f=0.70175,0.45505,0.00521:s
f=0.03213,0.17029,0.53110:s
f=0.22014,0.25707,0.88199:s

After wannierisation, the final center is

  WF centre and spread    1  ( -2.420986,  1.613991,  0.806995 )     0.58022873
  WF centre and spread    2  ( -1.613990,  0.806995,  2.420986 )     0.58022875
  WF centre and spread    3  ( -0.806995,  0.806995, -0.000000 )     0.58022874
  WF centre and spread    4  ( -1.613991,  1.613990, -0.000000 )     0.58022873

However the lattice parameter is

                    a_1    -1.613990   0.000000   1.613990
                    a_2     0.000000   1.613990   1.613990
                    a_3    -1.613990   1.613990   0.000000

so several centers is out of home cell.

According to user guide, I set options

translate_home_cell=true
write_xyz=true

re-run whole process, I got the content of .xyz file is still the same. This doesn't bring wannier center to home cell.

X         -2.42098572       1.61399050       0.80699526
X         -1.61399048       0.80699524       2.42098570
X         -0.80699525       2.42098572       1.61399048
X         -0.00000002       1.61399047       1.61399048
C          0.40349762      -0.40349762      -0.40349762
C         -0.40349762       0.40349762       0.40349762

Am I misunderstand the purpose of translate_home_cell? what is the usage of translate_home_cell?

Besides, there is also an option called translation_centre_frac. I tried to set it as

translation_centre_frac=(/0.,0.,0./)

However, nothing changes. So the second question: what is the purpose of translation_centre_frac?

_______________________________________________
Wannier mailing list
Wannier at quantum-espresso.org<mailto:Wannier at quantum-espresso.org>
http://mailman.qe-forge.org/cgi-bin/mailman/listinfo/wannier

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/wannier/attachments/20170501/1391e623/attachment.html>