BSE-Error

[Sam-2025]

Dear all,


I am running the following link(https://wiki.yambo-code.eu/wiki/index.p ... ter_kernel) as a benchmark and got the following error:

[ERROR] STOP signal received while in[05.01.05.03] Main kernel loop
[ERROR] Writing File ./3D_BSE//ndb.BS_Q1_CPU_0; Variable L_kind; NetCDF: Attempt to convert between text & numbers

Could you please guide me why this is happening.
Also for editing input file from RL unit to mRy(https://wiki.yambo-code.eu/wiki/index.p ... _screening), I have this error:
[ERROR] Initialization not yet done. Use RL units in the input or run initialization

Thank you so much for your guidance in advance.

[Daniele Varsano]

Dear Samira,

to spot the problem, you should provide more information: input and reports.
Anyway, it seems you are using an old version of the code. First of all I suggest you to download the last release of the code (yambo-5.3).

Best,

Daniele

[Sam-2025]

Dear Dr. Daniele Varsano,

Thank you so much for your guidance. Yes I am using Version 5.2.0 Revision. Sorry for exciton phonon coupling calculation( in the following page:https://wiki.yambo-code.eu/wiki/index.p ... minescence ), I should use Yambo version > 6.x ?
Also could you please let me know that in the BSE section , when I created the input file using command :yambo_ph -X s -o b -y d -V qp -k sex , how should I run it ? I mean using which command ? Thank you so much for your valuable guidance.

[Daniele Varsano]

Dear Samira,
my suggestion is to use the last release of the code (5.3).
Next, I suggest you to follow some yambo tutorials to become familiar with the code and convergence test., as the ones you can find in this page, or other in the tutorial wiki page:

https://wiki.yambo-code.eu/wiki/index.p ... #Tutorials

In general, once you have generated the input file, you can run it by typing:

yambo -F input_filename

Finally, please, pay attention to the warning written in red at the end of the tutorial on exciton-phonon coulpling.

Best,

Daniele

[Sam-2025]

Dear Dr. Daniele Varsano,

Thank you so much for your valuable guidance. I apologize for the confusion regarding the link, which states we should use Yambo version greater than 6.x. However, the most recent Yambo version I can find is 5.3. Am I misunderstanding something?

https://wiki.yambo-code.eu/wiki/index.p ... minescence


Additionally, regarding the gauge problem, I was advised to consult the following resource: https://github.com/yambo-code/LetzElPhC/tree/main. Dr. Varsano, do you believe that if my photoluminescence (PL) results do not match the experimental data, employing the method described in this link could help address the phase mismatch issue? Or is this feature still under development?

[Daniele Varsano]

Dear Samira,

the most recent version of Yambo is 5.3, so what's reported in the tutorial is a typo.

The LetzElPhC code indeed fixes the phase issue. Anyway, this is a very new implementation and I'm not expert in its usage.

Best,

Daniele

[Sam-2025]

Dear Dr. Daniele Varsano,

Thank you so much for your valuable guidance. My sincere appreciation.


With warm regards,
Samira.

[Sam-2025]

Dear Dr. Daniele Varsano,

Apologies for bothering you again, and thank you so much for your continued patience and support.

Following the tutorial "https://wiki.yambo-code.eu/wiki/index.p ... minescence" , I successfully generated the QPT12/dvscf/bn.save directory. In the next step, I began calculating the BSE for all momentum from within the" QPT12/dvscf/bn.save" directory using the command:
yambo_ph -X s -o b -y d -V qp -k sex

May I kindly ask if you think I am following the tutorial correctly? For instance, should I generate a new SAVE folder specifically for the BSE run (to obtain exciton wavefunctions), or is it correct to proceed BSE using the existing QPT12/dvscf/bn.save folder?

Dear Dr. Varsano, when I am continue the BSE steps from directory using QPT12/dvscf/bn.save folder, it gave me the following errors :

[ERROR] STOP signal received while in [07.01.05.03] Main kernel loop
[ERROR] Writing File ./3D_BSE//ndb.BS_Q1_CPU_0; Variable L_kind; NetCDF: Attempt to convert between text & numbers

I am working to install new version of Yambo but I am thinking maybe I misunderstood the tutorial. Thank you so much.

[Daniele Varsano]

Dear Samira,

I'm not an expert on the workflow you are following, maybe others can guide you through it.
From the error you get, anyway, it seems you are using an old version of the yambo code which is CPU dependent.
And please note, as reported in the tutorial:

Notice that this version is not fully tested therefore we advice you do not use it in production.

This is a very new implementation, and it is possible that it has not been extensively tested.

Best,
Daniele

[claudio]

Dear Samira

that tutorial was tested with the version linked in the tutorial, please use that one.
We are working on a new version of exciton-phonon coupling in Yambo, that will also solve the phases problem and simplify all the procedure.
This version will be available soon

best regards
Claudio Attaccalite