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<body class='hmmessage'><div dir='ltr'><div>Thanks for the Reply.</div><div><br></div><div><br></div>The negative frequencies are not just at gamma but along the axis of k vector (please check attachment for phonon dispersion png)<div><br></div><div><br></div><div><div>>> If somewhere else, you have a phase instability and a soft phonon mode </div><div><br></div><div>>>(if it's a <span style="font-size: 12pt;">charge density wave, not evident say GGA will be good enough)</span></div></div><div><span style="font-size: 12pt;"><br></span></div><div><span style="font-size: 12pt;"><br></span></div><div><span style="font-size: 12pt;">Was not able to get what did you </span>meant<span style="font-size: 12pt;">? As for the literature almost all work on the 2D tin has been done using VASP.</span></div><div><span style="font-size: 12pt;"><br></span></div><div>Can you inform me what general procedure you do recommend for the geometry optimization and relax.</div><div><br></div><div>I am using phononpy for the phonon dispersion calculation as I was not able to get documentation regarding q2r.x and matdyn.x </div><div><br></div><div><br></div><div>Regards,</div><div><br></div><div>Ghadiyali Mohammed Kader.</div> </div></body>
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