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</div><div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;">Yes, it’s implemented in matdyn, as the Invariance conditions are made on real-space force constants. For q2r, there is a related tag “write_lr” due to this implementation, to deal with the subtlety of long-range interactions in polar solids.</div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;"><br></div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;">One can find an example input in QE test suite for 2D phonon calculations with those corrections:</div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;"><a href="https://gitlab.com/QEF/q-e/-/tree/develop/test-suite/ph_2d" _src="https://gitlab.com/QEF/q-e/-/tree/develop/test-suite/ph_2d">https://gitlab.com/QEF/q-e/-/tree/develop/test-suite/ph_2d</a> <br></div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;"><br></div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;">Best,</div><div style="font-family: Helvetica, Helvetica, 微软雅黑, 宋体;">Changpeng</div></div>
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<a class="mail-from" style="color: #3061f2; text-decoration: none" href="mailto:nicola.marzari@epfl.ch">Nicola Marzari<nicola.marzari@epfl.ch>
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10/25/2023 17:02
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Changpeng Lin<changpeng.lin@epfl.ch>
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Re: [QE-users] Born Huang and Huang invariance conditions
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<div id="ntes-pcmail-quote" style="margin: 0; padding: 0; font-size: 14px; font-family: ''Helvetica','Microsoft Yahei', '微软雅黑'';"><br><br>Thanks - thhis is the paper:<br><br>https://www.nature.com/articles/s41524-022-00920-6<br><br>and in the matdyn <br>(https://www.quantum-espresso.org/Doc/INPUT_MATDYN.html) this is the <br>option 'all'.<br><br>Not sure about q2r - should be there as well, but I do not see it - but <br>maybe I'm missing something?<br><br> nicola<br><br><br><br>On 25/10/2023 16:44, Elio Physics wrote:<br> <blockquote class="mmbqc1">Dear all,<br> <br> There have been several papers discussing the use of the so-called <br> Born-Huang and Huang invariance conditions to soothe the possible <br> negative frequencies that may arise in the long wavelength limit (q->0, <br> near the G point) in the phonon dispersion of 2D and 1D material.<br> <br> Is there a specific flag in the ph.x input file that needs to be turned <br> on to incorporate such corrections?<br> <br> Regards<br> <br> Elie Moujaes<br> Adjunct professor level 4<br> Federal University of Rondonia<br> Brazil<br> <br> _______________________________________________<br> The Quantum ESPRESSO community stands by the Ukrainian<br> people and expresses its concerns about the devastating<br> effects that the Russian military offensive has on their<br> country and on the free and peaceful scientific, cultural,<br> and economic cooperation amongst peoples<br> _______________________________________________<br> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)<br> users mailing list users@lists.quantum-espresso.org<br> https://lists.quantum-espresso.org/mailman/listinfo/users<br></blockquote><br>-- <br>----------------------------------------------------------------------<br>Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL<br>Director, National Centre for Competence in Research NCCR MARVEL, SNSF<br>Head, Laboratory for Materials Simulations, Paul Scherrer Institut<br>Contact info and websites at http://theossrv1.epfl.ch/Main/Contact<br><br></div>
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