Dear all,
I have two questions.
First, for phonon spectra, we found some negative frequencies. I want to know whether the negative frequencies in solid can be called as soft model , i.e., negative frequencies and soft models have the same meanings in solid?
( It is well known that negative frequencies in molecules or clusters are usually used to indicate transtion states)
Second, through the "VibrationalMode", can we obtain the specific vibration of a negative frequency?
Thank you very much for your reply.
