Author Topic: Phonon transmission with bigger supercell for electrodes  (Read 105 times)

0 Members and 1 Guest are viewing this topic.

Offline chem-william

  • New ATK user
  • *
  • Posts: 5
  • Country: dk
  • Reputation: 0
    • View Profile
Hi, I'm trying to calculate the phonon transmission of different junctions with gold electrodes and a molecule in the middle. I'm a bit concerned about the resulting transmission as I've got substantial transmission at 0 omega (transmission > 1.0). I took a look at the settings that the dynamical matrix was calculated with and it said the following:
Code
repetitions                        = (1, 1, 3)
which makes sense given I've told it to only make 1, 1, 1 repetitions in the settings for the dynamical matrix. But, what I suspect is that this is not enough for the phonons to go to zero and that's why I get such high transmission at omega = 0. Is there any way to only make a bigger supercell for the electrodes, but not the unit cell? I'd like to avoid repeating the central region as it substantially increases the time to calculate the dynamical matrix.