Electron Phonon Coupling

[WEIW]

Dear Daniele,
When calculating the optical properties at a finite temperature, I found that the command -X s cannot take effect. I think that it may come from the previous quasi-particle calculation problem, because there is no GW correction in the quasi-particle band gap including electron phonon coupling, and the output file seems to have the correction only caused by temperature. In the quasi-particle calculation, I used the command line yambo_ph -g n -p fan -c ep -V gen in the tutorial. The relevant input files and results are attached below.


Best,
Liu.

[SAM]

dear yambo user,
please I have a concern. In order to do luminescence calculations I am doing phonon calculations which crashes every time. here are the calculation steps that I did:
1- scf calculation
2- nscf calculation
3- reading the qpoints in the SAVE of the calculation
4- phonon calculation (with the qpoints obtained from yambo)
unfortunately this calculation crashes every time.

Here is the error obtained: task # 0
from initialize_grid_variables : error # 1
problems reading u

my input file for phonon calculation :
&inputph
verbosity = 'high'
tr2_ph = 1e-12
prefix = 'hBN'
fildvscf = 'hBN-dvscf'
fildyn = 'hBN.dyn'
electron_phonon = 'dvscf',
epsil = .false.
trans = .false.
ldisp = .false.
qplot = .true.
/
14
0.000000000 0.000000000 0.000000000 1
0.000000000 0.000000000 0.193648323 1
0.000000000 -0.192450061 0.000000000 1
0.000000000 -0.192450061 0.193648323 1
0.000000000 -0.384900123 0.000000000 1
0.000000000 -0.384900123 0.193648323 1
0.000000000 0.577350199 0.000000000 1
0.000000000 0.577350199 0.193648323 1
-0.166666672 -0.288675100 0.000000000 1
-0.166666672 -0.288675100 0.193648323 1
-0.166666672 -0.481125146 0.000000000 1
-0.166666672 -0.481125146 0.193648323 1
-0.333333343 -0.577350199 0.000000000 1
-0.333333343 -0.577350199 0.193648323 1

please help me

SAM
PhD student at University of Lome/Togo

[Davide Sangalli]

Dear Sam,
did you try to follow these tutorials:

- https://www.yambo-code.eu/wiki/index.ph ... n_Coupling
- https://www.yambo-code.eu/wiki/index.ph ... placements
- https://www.yambo-code.eu/wiki/index.ph ... minescence

Best,
D.

[SAM]

Dear Davide,

Thank you very much for your answer. I tried this tutorial except that I had a problem with the bash ./rundvscf. But now it's good. However, I have a concern about the tutorials on calculating the lifespan of excitons which is located just after the calculation of luminescence: yambo -excph l command does not work for me

[Daniele Varsano]

Dear Sam,

I think it should be:
>yambo_ph -excph

Please sign your post with your name and affiliation, it is a rule of the forum and you can do once for all by filling the signature in your profile.

Best,
Daniele

[SAM]

Dear Daniele,
Thanks you for your respons.

SAM
PhD student
University of Lome/Togo

[SAM]

Dear
I have a problem with the luminescence calculation. When I do the calculation I get the following output
But the calculation on the dispersion of excitons works

Found Lout with dimension: 576 x 576
L kind out: BAR
Found Lin with dimension: 576 x 576
L kind in: BAR
Use coupling convention from: PALEARI
[RD./SAVE//ndb.elph_gkkp_expanded]----------------------------------------------
Brillouin Zone Q/K grids (IBZ/BZ) : 19 144 19 144
Fragmentation : yes
[ELPH] Phonon modes : 12
[ELPH] Q points : 144 [avail]
[ELPH] K points : 144
[ELPH] El-PH bands : 1 16
[ELPH] Using the Q-grid : yes
[ELPH] Bare interaction : no
[ELPH] Debay-Waller : yes
- S/N 005530 ---------------------------------------------- v.05.02.00 r.22427 -

[ERROR] STOP signal received while in[04] Excitonic gkkp

[ERROR] Q-points do not match

SAM
PhD student
University of Lome/Togo

[claudio]

Dear SAM

are you following this tutorial?

https://www.yambo-code.eu/wiki/index.ph ... minescence

have you downloaded the Yambo version mentioned in the tutorial?

best
Claudio

[SAM]

Dear Claudio,

Thank you for answering me.

I'm actually following this tutorial. I did the dispersion calculation successfully and got the curves obtained. However the difficulty lies just after I execute the command: yambo_ph -excph o
the error I get: Says el-ph data is not found

SAM
PhD student at university of Lome