Yambo Community Forum

Dear all,
Thanks for your attention. I want to get transition dipole moment after BSE calculations. But I don't know how to get it via Yambo.
& ypp -J 2D_WR_WC -e s 1,
The dipole oscillator strength of excitons can be obtained. So can I get the transition dipole moment data via the dipole oscillator strength ? If so, how can I do this ?
In the framework of Fermi’s Golden rule, I will use the transition dipole moment to estimate the radiative recombination lifetimes, which are already computed in BSE simulations.
Calcualtion Methods for Radiative Lifetimes, I refer to this literature, in which the Yambo code is adopted.
Exciton Radiative Lifetimes in Two-Dimensional Transition Metal Dichalcogenides, Maurizia Palummo,† Marco Bernardi,‡ and Jeffrey C. Grossman*, Nano Lett. 2015, 15, 2794−2800.

If you have any experience regarding this, please guide me through it and I would greatly appreciate it.

Best wishes to you!
Yours sincerely,
Luo Yan

Dear Luo Yan,

you can use the yambo-py platform to read databases (both dipoles and BSE eigenvector) to build the observable you aim to calculate.
Here you can find a yambo-py tutorial to read Yambo databases.
https://wiki.yambo-code.eu/wiki/index.p ... _databases

Best,

Daniele

Dear Professor,
Thanks for your help. Following the "Dipoles intro: plots of dipoles on BZ, plot of IP absorption" tutorial part (https://wiki.yambo-code.eu/wiki/index.p ... absorption),
I used the script dipoles_plot.py to abstract the transition dipole moment.
In my opinion, the transition dipole moment data may be stored in ndb.dipoles. I am not sure about this.
However, I got just a little bit of information, and it wasn't the dipole moment I was looking for.
The script and the text I extracted are in the attachment. Looking forward to your further assistance.
Best wishes to you!

Yours sincerely,
Luo Yan

Dear Luo,

dipoles <v|r|c> are stored in the ndb.dipoles database, while BSE eigenvector (Acvk) can be read from ndb.BS_diago.
From these two quantities you should be able to calculate the radiative lifetime as described in the reference you pointed out.

Best,
Daniele