Error (nan) in Pop_frequency calculation using AMSET

Dear Alex and kind users,
When I use amset to calculate POP-frequency, after typing: “amset phonon-frequency”, I got the info like this: Frequency Weight

  Frequency    Weight
-----------  --------
       0.00       nan
       0.00       nan
       0.00       nan
      23.35       nan
      23.35       nan
      23.35       nan
      23.35       nan
      23.35       nan
      23.35       nan
      31.72       nan
      31.72       nan
      31.72       nan
      31.72       nan
      31.72       nan
      31.72       nan
      35.68       nan
      35.68       nan
      35.68       nan
      35.68       nan
      35.68       nan
      35.68       nan
      38.73       nan
      38.73       nan
      38.73       nan

pop_frequency: nan THz

How can I solve this problem and get pop frequency?

Please can you send me your OUTCAR and vasprun.xml

Dear Alex:
My INCAR,vasprun.xml and OUTCAR are:

INCAR (611 Bytes)
vasprun.xml (571.4 KB)
OUTCAR (577.3 KB)

Hi @chenjiashu,

In this case your system only contains a single element type (carbon) and therefore is not polar. Accordingly, there will be no polar optical phonon scattering (as no phonons will generate a dipole).

In this case you don’t need to set pop_frequency in the input file.

I will update the command line tools so that they give a more reasonable error message.

Best,
Alex

Dear Alex,

You are very generous and kind! Thank you very much!

Best wishes,
Chenjiashu