[Wannier] How to select projections?

[Mostofi, Arash]

Dear Zongyi
The projections block in this example contains 12 projection functions. The first four lines correspond to s-orbitals centred on Si-Si bonds; the fifth line corresponds to 8 sp3 hybrid orbitals centred on the two Si atoms in the unit cell (4 on each). For calculating MLWFs for the 4 valence bands only, the first 4 projections are selected (projections 1-4 in the list); for calculating MLWFs for the composite group of 4 valence bands and 4 lowest-lying conduction bands, the 8 sp3 hybrid orbitals are selected (projections 5-12 in the list, although I understand your confusion because these are compressed into a single entry in the input file).
Hope this helps,
Arash

—
Professor Arash Mostofi
Department of Materials
Imperial College London

On 18 Jun 2024, at 08:32, wangzongyi at mail.ustc.edu.cn wrote:

Dear all
I am puzzle in how to write the parameter of select_projections when calculate the valance band. This is part of the program given by Wannier90 tutorial_12
begin projections
!! !! Bond-centred s-orbitals
f=-0.125,-0.125, 0.375:s
f= 0.375,-0.125,-0.125:s
f=-0.125, 0.375,-0.125:s
f=-0.125,-0.125,-0.125:s
!! !! Atom-centred sp3-orbitals
Si:sp3
end projections
!! (1) Valence bands
num_wann        =   4
select_projections 1 2 3 4
dis_froz_max    =   6.5
dis_win_max     =   6.5

!! !! (2) Valence + conduction bands
!! num_wann        =   8
!! select_projections 5-12
!! dis_froz_max    =   6.5
!! dis_win_max     =  17.0

I can't understand why the program select select_projections 1 2 3 4 when calculating valance band, while choose select_projections 5-12 to calculate valence and conduction bands? Which file can tell me the mean of the labels, so that I can write select_projections correctly?
Could you please help me? Thank you very much!

Zongyi Wang

_______________________________________________
Wannier mailing list
Wannier at lists.quantum-espresso.org<mailto:Wannier at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/wannier

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/wannier/attachments/20240618/11aa294f/attachment-0001.html>