EPW Forum

Dear all,

I am calculating the EPC of my system. After wannierization, I fonund a small part of phonon is too stange when I plotted the band structure and phonon, as shown in the figure below,


Why it happened?

BTW, the version I used is v5.8， and the dense k-mesh and q-mesh are 48*48*48 and 24*24*24, respectively.

Thanks and regard!

Jianguo Si

Hi Jianguo Si,

Could you double check your 'selecq.fmt' file and make sure all the q-points along the high symmetry path are included? It looks like those q-points are excluded in your calculation.

Happy EPWing,
Hari

Hi Hari,

Thanks for you kindly reply.

I have checked selecq.fmt and find that it inculde all q points (total 13824 points with a 24*24*24 dense q-mesh), as shown in the following figure. Besides, I check the band structure calculated with same high symmetry path, it is consistent well with the DFT one. So I'm still confused.

Thanks again!
Jianguo

Hi Jianguo,

I think the problem comes from the fsthick. Increase the fsthick size or use etf_mem=0 in your epw input file. If that does not help, please check the q-point path that it does not have any discontinuity.

Best regards,
Sabya.

stiwari wrote: ↑Fri Oct 11, 2024 1:36 am Hi Jianguo,

I think the problem comes from the fsthick. Increase the fsthick size or use etf_mem=0 in your epw input file. If that does not help, please check the q-point path that it does not have any discontinuity.

Best regards,
Sabya.

Hi Sabya,

Thanks for your kindly relpy, I will try with your suggestion. Hope for better results.

Thanks again and respect!

Jianguo