<html><head></head><body><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div><div>Hi</div><div>1- Use parallel version</div><div>2- A bad converged structure (with low threshold) may give large negative phonons.</div><div>3- Use very tight SCF convergence<br></div><div><br></div><div><br></div><div class="ydp82f19a5fsignature">Regards<br> <br> David</div></div>
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On Wednesday, November 29, 2017, 10:42:44 AM GMT+3:30, Suresh A <suresh2007pgp19@gmail.com> wrote:
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<div><div id="ydp3f62cfa4yiv9071873048"><div dir="ltr"><div><div><div>Dear All,<br></div> I am ran phonon calculation for anatase previously and got negative frequencies. I was install QE-5.2.0 in serial mode and took days to finish the calculation in my desktop.<br><br></div>Is there any way to know the negative frequency before the calculation ends? So that the time can be saved.<br></div> Thank You <br><div><div><div><div> <br clear="all"><div><div><div><div class="ydp3f62cfa4yiv9071873048gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div><div><div style="margin-left:40px;text-align:right;"> Yours Sincerly,<br><br></div><div style="text-align:right;">A.Suresh,<br></div></div><div style="text-align:right;">Research Scholar,<br></div><div style="text-align:right;">School of Physics,<br></div></div><div style="text-align:right;">Madurai Kamaraj University,<br></div></div><div style="text-align:right;">Madurai.<br></div></div></div></div></div></div></div></div>
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