[Phonopy-users] Negative Frequencies

[وجود ا. ه. د. <wd...@ka...>]

Hi,
I have a system with 60 atoms. I've built  2x2x1 supercell using phonopy
and got 240 supercell files with displacements with 240 atoms. I calculated
the forces using pwscf and manged to get the bands and Dos. The problem is
that i got some negative frequencies as can be seen on the attached bands
and dos figures. Is there a way to get rid of these frequencies as its
difficult to go to higher dimension of supercell like 3x3x1??
Best Regards
Wajood


Dr. Wajood A. Diery
Assistant Professor
Physics Department, Faculty of Science
King Abdulaziz University
Jeddah, Saudi Arabia
Email: wd...@ka... <wd...@ka...>
Website: http://wdairy.kau.edu.sa

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