QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: AsifShah on June 30, 2022, 11:28

Title: Bandstructures
Post by: AsifShah on June 30, 2022, 11:28

Dear Admin/Anyone,
Could you kindly explain why any multiple of 3 chosen for a supercell (in this case for moS2) produces a different bandstructure than other sizes. It can be seen below that for a supercell of 3x3 & 9x9 we have VBM & CBM along G point whereas for other sizes such as 4x4,5x5 it is along KM points?
 Is it something with software or I am missing something here?
See the attachment below

Title: Re: Bandstructures
Post by: Anders Blom on July 6, 2022, 06:50

Always plot band structures in the primitive cell, else you are folding the Brillouin zone for unexpected results. The K and M points in a supercell are not the same as in the primitive cell.

Title: Re: Bandstructures
Post by: AsifShah on July 6, 2022, 06:59

Thanks or your response.
That said, wont it affect my other calculations when working with supercell of multiple of 3 unit cells? Should I be then avoiding a supercell of multiple of 3 unit cells or it is okay to continue with them?

Title: Re: Bandstructures
Post by: Anders Blom on July 8, 2022, 20:25

No, the results are still correct for the supercell, it's just how you interpret them in the band structure plot that gets confusing.