[Wannier] about initial projections in seedname.win

[Duk-Hyun Choe]

Dear Wannier developers and users,

 I am new to the Wannier90 code and trying to calculate the polarization of
bulk BaTiO3.

 I think the bulk polarization should not depend on the choice of initial
projections once the convergence has reached but, strangely enough, the
results seem to depend on the initial projections schemes.

 For example, I tested two initial projections for BaTiO3.

Case #1: atomic orbital projections
dis_num_iter = 80000
dis_mix_ratio = 0.9d0
dis_conv_tol = 1.0d-9

conv_window  = 100
conv_tol = 1.0d-9

search_shells = 50

*Begin Projections*
*Ba: s;px;py;pz*
*O: sp3*
*End Projections*

guiding_centres = true
#num_no_guide_iter = 20

num_iter = 80000
num_print_cycles = 100

use_bloch_phases = F

write_r2mn = true
write_xyz = true

num_bands = 32
num_wann = 16
===========================================

Case #2: random projections
dis_num_iter = 80000
dis_mix_ratio = 0.9d0
dis_conv_tol = 1.0d-9

conv_window  = 100
conv_tol = 1.0d-9

search_shells = 50

*Begin Projections*
*Random*
*End Projections*

guiding_centres = true
#num_no_guide_iter = 20

num_iter = 80000
num_print_cycles = 100

use_bloch_phases = F

write_r2mn = true
write_xyz = true

num_bands = 32
num_wann = 16

===================================================

The only difference in the two input files is the Projections block.

Although both cases are converged, the sum of wannier centers for the
occupied bands are different for case 1 and case 2.

Can anyone help me with this?

Any comment and/or suggenstions would be very much appreciated.

Thank you.

Best,

*|** Duk-Hyun Choe*, Post-doctoral fellow,
  Department of Physics, Applied Physics, and Astronomy
  Rensselaer Polytechnic Institute, Troy, NY, USA
  E-mail: hoalad at gmail.com,  Tel: +1-518-687-4389
  Home: https://sites.google.com/site/dhchoeprofile/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/wannier/attachments/20190325/ce825b3d/attachment.html>