QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: javispain on April 5, 2017, 15:56

Title: Lattice thermal conductivity
Post by: javispain on April 5, 2017, 15:56

Good afternoon


I am trying to calculate the lattice thermal conductivity for a fcc crystal. I read the tutorials, and I really think that this program can be a good choice to perform these calculations. However, I would like to solve some doubts:

1.- According to the tutorials, This software allows to calculate the thermal conductivity for interfaces, but have you tested these calculations with large crystals? I imagine so. And I have tried it with small supercells -around 8x8x50 unit cells-, but I think that the software does not allows to create supercells larger than 100x100x100 - although they can be created manually. Why? Is it not necessary to use such a large supercell to obtain good results?

2.- I am a PhD student, but I would need a professional license to perform simulation in a cluster. Would I have problems with a professional license because of the different mac addresses?

Thanks a lot for your attention.


Kind regards,

Javier

Title: Re: Lattice thermal conductivity
Post by: Petr Khomyakov on April 5, 2017, 23:00

Regarding #1, why would you need to use millions of atoms to calculate the thermal conductivity of a crystalline material? I guess you may do several calculations for much smaller supercells to see how fast the conductivity converges to a certain value.

Title: Re: Lattice thermal conductivity
Post by: javispain on April 6, 2017, 11:08

It would be because usually 4x4x1000 cells or similar are used for this purpose, but you are right when saying that it is better for me to look for a good convergence with smaller supercells.

Thanks!