PDOS w/ Imaginary Frequencies


I’ve been using GULP to calculate phonon modes for instantaneous liquid configurations which exhibit imaginary frequencies (I think solids near melting point also do this). It does this perfectly; however, the .dens file created by the “output phonon” command does not include the imaginary frequencies in its calculation. Is there someway to include these frequencies in the PDOS as negative numbers? GULP already uses that convention for the frequency output.

I attached the input and outputs incase that is helpful.
LJ_liq.gin (12.2 KB)
LJ_liq_phon.dens (1.7 KB)
LJ_liq (9 KB)


If you add the keyword “include_imaginary” then imaginary modes should be included in the output.

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