Author Topic: G0W0 - k-point related error message  (Read 26 times)

0 Members and 1 Guest are viewing this topic.

Offline hagelberg

  • Regular QuantumATK user
  • **
  • Posts: 18
  • Country: us
  • Reputation: 0
    • View Profile
G0W0 - k-point related error message
« on: Today at 15:41 »
Hello -
This is about a G0W0 calculation on a nanoribbon system. The job fails with the error message
"The k-point sampling needs to be a least '5' in each direction for metallic systems, if a Gamma-point correction is used."
Some comments:
(1) Even the minimal choice of 5x5x5 makes my system prohibitively large.
(2) As the system is one-dimensional, it should be possible to select k_x = k_y = 1 for the non-periodic directions.
(3) Since the system is an AFM zigzag nanoribbon, it should be semiconducting (the expected bandgap is around 0.8 eV), and so the metallicity assignment looks like a misdiagnosis.
(4) Setting 'include_gamma_point=False' does not seem to change anything.
My question, therefore: Is there any way around the k-points constraint for G0W0 calculations?

Please find the respective .py input file attached. I'm using QuantumATK-X-2025.6.
Thanks a lot,
Frank Hagelberg