<div dir="ltr"><div>If your idea is to select a subset of atoms and compute the dynamical matrix for that subset of atoms only, I do not think you wiell ever get reasonable numbers. <br></div><div><br></div><div>Paolo<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Nov 5, 2019 at 7:06 PM thorgalg <<a href="mailto:thorgalg@poczta.onet.pl">thorgalg@poczta.onet.pl</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>Dear Christian,<br><br>I spend the last two weeks testing this setting (nat_todo=16).<br><br>My system contains more than 200 atom and was optimized <br>until the forces on all the atoms were less than 0.02 eV/A.</div>
<div>Then, I wanted to calculate the zero-point-energy (zpe) correction <br>for the adsorbed molecule (benzene derivative) using ph.x. Unfortunately, <br>I obtained a lot of imaginary frequencies (at the beginning of dynamical <br>matrix in the ph.out file ):<br><br> freq ( 1) = -98.010682 [THz] = -3269.284435 [cm-1]<br> freq ( 2) = -95.651863 [THz] = -3190.602722 [cm-1]<br> freq ( 3) = -72.672472 [THz] = -2424.092724 [cm-1]<br> freq ( 4) = -71.325508 [THz] = -2379.162841 [cm-1]<br> freq ( 5) = -66.443681 [THz] = -2216.322637 [cm-1]<br> freq ( 6) = -63.174512 [THz] = -2107.274901 [cm-1]<br> freq ( 7) = -61.771254 [THz] = -2060.467247 [cm-1]<br> freq ( 8) = -59.520061 [THz] = -1985.375532 [cm-1]<br>...<br>...<br><br>Then, when I wanted to calculate the dynamical matrix, the program <br>(dynmat.x) stuck on attemption the asr calculation.<br><br>....<br>Acoustic Sum Rule: || Z*(ASR) - Z*(orig)|| = 0.000000E+00<br><br><br>The input file for dynmat.x is:<br><br>&input<br> fildyn = 'benz_surf.dyn'<br> asr = 'zero-dim'<br>/<br><br>If this setting will work properly, it would be very helpful for all these QE</div>
<div>users working on the theoretical catalysis. <br><br>Best,<br><br>Tomasz Krol<br>Cracow University of Technology</div>
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<div>W dniu 2019-11-05 17:42:13 użytkownik Hari Paudyal <<a href="mailto:hpaudya1@binghamton.edu" target="_blank">hpaudya1@binghamton.edu</a>> napisał:</div>
<blockquote style="margin-left:7px;border-left:2px solid orange;padding-left:8px">
<div dir="ltr">Hi Christian,
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<div><span style="color:rgb(0,0,0);font-family:arial,helvetica,sans-serif;font-size:medium;font-weight:bold;background-color:rgb(255,255,153)">nat_todo</span> can be used to c<span style="color:rgb(0,0,0);font-size:14px">hoose the subset of atoms to be used in the linear response </span><span style="color:rgb(0,0,0);font-size:14px">calculation. Please have a look if that is under your interest.</span></div>
<div><span style="color:rgb(0,0,0);font-size:14px"> </span></div>
<div><span style="color:rgb(0,0,0)"><span style="font-size:14px">Best,</span></span></div>
<div><span style="color:rgb(0,0,0)"><span style="font-size:14px">Hari Paudyal</span></span></div>
<div><span style="color:rgb(0,0,0)"><span style="font-size:14px">SUNY, Binghamton</span></span></div>
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<div dir="ltr">On Tue, Nov 5, 2019 at 11:26 AM Christian helman <<a>christian.helman@gmail.com</a>> wrote:</div>
<blockquote style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi<br> I just calculate an interface between two compounds. No problem and<br> results are as expected.<br> however I would like to calculate the phonons at the interface (even<br> more electron -phonon coupling but let's start with just phonons).<br> Since my unit cell is huge, my question is :<br> is there any way to calculate the phonons "only at the interface" by<br> allowing to move the interface atoms ?? something like "selective<br> dynamics"<br> Thanks in advance<br> <br> -- <br> Dr. Christian Helman<br> Departamento de Neutrones y Reactores<br> Centro Atómico Bariloche -CNEA<br> Ezequiel Bustillos 9,500 Km - CP 8400<br> San Carlos de Bariloche<br> Provincia de Rio Negro, Argentina<br> Tel:++54-294-444-5100 int 5308<br> _______________________________________________<br> Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu/quantum-espresso" rel="noreferrer" target="_blank">www.max-centre.eu/quantum-espresso</a>)<br> users mailing list <a>users@lists.quantum-espresso.org</a><br> <a href="https://lists.quantum-espresso.org/mailman/listinfo/users" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></blockquote>
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Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu/quantum-espresso" rel="noreferrer" target="_blank">www.max-centre.eu/quantum-espresso</a>)<br>
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<a href="https://lists.quantum-espresso.org/mailman/listinfo/users" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div>Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,<br>Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br>Phone +39-0432-558216, fax +39-0432-558222<br><br></div></div></div></div></div>