Dear developers,
I have calculate the phonons under the input file od 02ph.in, but the lowest 3 branches are negative at gamma point. Does this affect the final
results? If so, how could we avoid it.
Thanks!
negative phonon modes in el-ph calculation
Moderators: palful, amolina, mbonacci
-
sdwang
- Posts: 287
- Joined: Fri Apr 09, 2010 12:30 pm
-
amolina
- Posts: 135
- Joined: Fri Jul 15, 2011 11:23 am
- Location: Valencia, Spain
- Contact:
Re: negative phonon modes in el-ph calculation
Hi,
the example for phonons in yambopy is a non-converged test. Therefore the user must check the convergence parameters for getting reliable results. In addition, the acoustic phonons, the 3 lowest branches at gamma can have negative values. One solution is to apply the acoustic sum rule with the functions designed for that in Quantum Espresso (dynmat.x).
Best,
Alejandro
PS: Can you update your profile to include your signature?
the example for phonons in yambopy is a non-converged test. Therefore the user must check the convergence parameters for getting reliable results. In addition, the acoustic phonons, the 3 lowest branches at gamma can have negative values. One solution is to apply the acoustic sum rule with the functions designed for that in Quantum Espresso (dynmat.x).
Best,
Alejandro
PS: Can you update your profile to include your signature?
Alejandro Molina-Sánchez
Institute of Materials Science (ICMUV)
University of Valencia, Spain
Institute of Materials Science (ICMUV)
University of Valencia, Spain