regarding calculation of PhononTransmissionSpectra and TE coefficients

[Sushree Sarita Sahoo]

Dear Sir,
I am a new user for QuantumATK and for trial I wanted to calculate ZT value of a compound. Initially when I am trying to calculate the Phonon Transmission spectra, I am getting all the values as Zero. (I tried running the calculation in parallel but its running for days without any progress, then I checked the forum and tried in serial but the calculations are getting over in seconds with all the values as zeros).
Kindly help me in this regard and it would be really helpful if you can give some assistance on the calculation of ZT.
One more query: As the phonon transmission spectra and the transport coefficients are available for device configuration only. Can we use the Bulk to Device tool available in the Builder and proceed with these calculations? I tried this for my compound but not getting any values of transmission. Am I approaching it correctly or doing a mistake?
Waiting for your earnest response

Thanks and Regards

[Akash Ramasamy]

In the dynamical matrix,  in repetitions choose the custom option with default values. First, try it. Maybe you can get it.

[Anders Blom]

First make sure you can complete the tutorial example https://docs.quantumatk.com/tutorials/phonon_calcs/phonon_calcs.html, which I know is rather outdated and therefore a bit hard to follow. But it should be fast to run. After that you can try to generalize to some system of your own choice, but keeping the same logic and structure of the script.

[Sushree Sarita Sahoo]

How exactly shall we set the Force field potential for an unknown system whose predefined potentials are not available?

[karan1234]

http://docs.quantumatk.com/tutorials/mtp_basic/mtp_basic.html

You can go through the above mentioned tutorial to create your own force fields for any unknown system whose predefined potentials are not available.