Problem in wannierization

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rkarkee
Posts: 19
Joined: Fri Jul 07, 2023 2:49 pm
Affiliation: UC Merced

Problem in wannierization

Post by rkarkee »

Hi all,

I am trying to wannierise hfte5, with spin orbit couplings. Before doing EPW calculation, I am testing from wannier90 code whether my projections, and others looks good or not. I am having trouble in matching wannierized bandstructure with dft band structure. The first problem is there is mismatch in x-scale for bandstructure plot. For example, DFT band spans upto 3.64 in x-axis whereas bands from wannier90 code go only upto 3.09 in x-axis. I have tried to match k-path but band.labelinfo.dat has some inaccuracies. If you see below, band.labelinfo.dat lists X to gamma correctly but Gamma to Y incorrectly, as I am specifying 70 k-points in all high symmetry points. Because of this issue, I am unable to plot and check bandstructure together.

Also, I am not able to get good convergence (DLTA= -0.5338997E-03) for wannier functions. How can I fix this?
I have also asked this question in Wannier90 forum, but havent heard any responses yet. Can you please help me out here.


My input.win looks:

use_ws_distance = .true.
num_bands = 90
num_wann = 80
exclude_bands=1-132, 223-290
num_iter = 400
iprint=2

dis_win_max=14
dis_froz_max=13
dis_froz_min = 3
dis_win_min = 3

Begin Projections
Hf:d
Te:p
End Projections

bands_num_points=70

Begin Kpoint_Path
X 0.25122543 -0.25122543 0 G 0 0 0
G 0 0 0 Y 0.24908686 0.24908686 0
Y 0.24908686 0.24908686 0 S 0.5003123 -0.00213862 0
S 0.5003123 -0.00213862 0 R 0.5003123 -0.00213862 0.49836313
R 0.5003123 -0.00213862 0.49836313 Z 0 0 0.49836313
Z 0 0 0.49836313 G 0 0 0
End Kpoint_Path

bands_plot = .true.
spinors=true
! SYSTEM

begin unit_cell_cart
ang
1.98619742 7.132231003 0.
-1.986197815 7.132230891 0.
0. 0. 13.586526936
end unit_cell_cart

begin atoms_frac
Hf 0.3184997032 0.3184997302 0.7499999470
Hf 0.6815000238 0.6815000678 0.2499999640
Te 0.6625100716 0.6625100596 0.7499999470
Te 0.3374897664 0.3374897594 0.2499999640
Te 0.9351348779 0.9351349339 0.8531524632
Te 0.0648648561 0.0648648571 0.3531525342
Te 0.9351348779 0.9351349339 0.6468473588
Te 0.0648648561 0.0648648571 0.1468474118
Te 0.7919052147 0.7919052377 0.4336792513
Te 0.2080945513 0.2080945543 0.9336791443
Te 0.7919052147 0.7919052377 0.0663207087
Te 0.2080945513 0.2080945543 0.5663206417
end atoms_frac

! KPOINTS

mp_grid : 8 8 4

begin kpoints
0.00000000 0.00000000 0.00000000
0.00000000 0.00000000 0.25000000
0.00000000 0.00000000 0.50000000
0.00000000 0.00000000 0.75000000
0.00000000 0.12500000 0.00000000
0.00000000 0.12500000 0.25000000
0.00000000 0.12500000 0.50000000
0.00000000 0.12500000 0.75000000
0.00000000 0.25000000 0.00000000
0.00000000 0.25000000 0.25000000
0.00000000 0.25000000 0.50000000
0.00000000 0.25000000 0.75000000
0.00000000 0.37500000 0.00000000
0.00000000 0.37500000 0.25000000
0.00000000 0.37500000 0.50000000
........ and so on


The band.labelinfo.dat lists as:
X 1 0.0000000000 0.2512254300 -0.2512254300 0.0000000000
G 71 0.7947325667 0.0000000000 0.0000000000 0.0000000000
Y 90 1.0141672584 0.2490868600 0.2490868600 0.0000000000
S 160 1.8088999200 0.5003123000 -0.0021386200 0.0000000000
R 180 2.0393714681 0.5003123000 -0.0021386200 0.4983631300
Z 253 2.8638419524 0.0000000000 0.0000000000 0.4983631300
G 273 3.0943135005 0.0000000000 0.0000000000 0.0000000000

My bands calculation in dft has k-path as:
K_POINTS {crystal_b}
7
0.25122543 -0.25122543 0 70 !X
0 0 0 70 !G
0.24908686 0.24908686 0 70 !Y
0.5003123 -0.00213862 0 70 !S
0.5003123 -0.00213862 0.49836313 70 !R
0 0 0.49836313 70 !Z
0 0 0 1 !G

Whenever I plot dft band vs output from wannier90.x, I get mismatch in x-axis so that I am able to compare the results properly.
Also I have some convergence issue with this input, I am getting delta in final step as-0.5338997E-03 . How can I achieve better convergence and how to fix this band plot issue?

Thanks a lot.

Best
Rijan Karkee
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