I'm trying to simulate a small Silicon-Cristall, to get the Raman-Signal.
Following the tutorial of NLO, The calculation comes to an end in the anaddb run.
The errorcode is
Code: Select all
Electronic dielectric tensor
4072.93389323 -3711.12116148 3.55711257
-3711.12116148 4072.93389323 3.55711257
3.57613481 3.57613481 1.78547640
The lowest mode appears to be a "true" negative mode,
and not an acoustic mode. This precludes the computation
of the frequency-dependent dielectric tensor.
Action : likely there is no action to be taken, although you,
could try to raise your convergence parameters (ecut and k-points).
For your information, here are the four lowest frequencies :
-1.08523540E-03 -8.27428547E-04 -7.94477183E-04 -5.45799253E-04
If I check with a run, where the silicon is in full structure it is quite to the end.
Is there a way to remove the problematic modes from the calculation?
Attached is the out file.