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<div dir="ltr" data-setdir="false">I just tried but i got the following error message:</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">"</div><div dir="ltr" data-setdir="false"><div><div> Error in routine phq_readin (1):</div><div> gamma_gamma tricks with nat_todo not available. Use nogg=.true.</div></div><br></div><div>"</div><div dir="ltr" data-setdir="false">i'm doing single q phonon calculation </div><div dir="ltr" data-setdir="false">any help ?</div>
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On Wednesday, October 28, 2020, 05:45:15 PM GMT+4, Tamas Karpati <tkarpati@gmail.com> wrote:
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<div><div dir="ltr">Dear Omer,<br clear="none"><br clear="none">Did you try to use the nat_todo option in your PH.x input file?<br clear="none">(Do not forget to list the perturbed atom indices on the last line.)<br clear="none"><br clear="none">ASE can use QE as "calculator" and I think it can do what you want.<br clear="none">If not, use Phonopy.<br clear="none"><br clear="none">HTH,<br clear="none"> t<br clear="none"><div class="yqt3727004091" id="yqtfd81320"><br clear="none">On Wed, Oct 28, 2020 at 1:28 PM Omer Mutasim <<a shape="rect" ymailto="mailto:omermutasim@ymail.com" href="mailto:omermutasim@ymail.com">omermutasim@ymail.com</a>> wrote:<br clear="none">><br clear="none">><br clear="none">> Dear all<br clear="none">><br clear="none">> I need to calculate the the virbrational frequencies of adsorbate molecule on surface using phonon single q calculation , in order to estimate the partition function (for entropy ,reaction rate constants). so my questions go like:<br clear="none">><br clear="none">> I have a large supercell (110 atoms) which means a high degrees of freedom (330 DOF) , so i want to decrease this DOF , by perturbing only adsorbate molecule and the the two uppermost layers<br clear="none">><br clear="none">> how to select the perturbed atoms in quantum espresso ?<br clear="none">> I have heard that it can be done by finite difference method, which wasn't employed in QE.<br clear="none">> However, i have seen a post where Dr. Paolo Giannozzi said: " it can be performed by two finite-difference calculations with opposite displacements "<br clear="none">> So , can you please tell me, what are the steps involved in doing this finite-difference method mentioned by Dr. Paolo ? or any other procedure that can be do the same ?<br clear="none">><br clear="none">><br clear="none">> Thanks in advance<br clear="none">><br clear="none">><br clear="none">><br clear="none">><br clear="none">> Omer Elmutasim<br clear="none">> Research Assistant<br clear="none">> Chemical Engineering Department<br clear="none">> Khalifa university- UAE</div><br clear="none">> _______________________________________________<br clear="none">> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)<br clear="none">> users mailing list <a shape="rect" ymailto="mailto:users@lists.quantum-espresso.org" href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a><br clear="none">> <a shape="rect" href="https://lists.quantum-espresso.org/mailman/listinfo/users" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a><br clear="none">_______________________________________________<br clear="none">Quantum ESPRESSO is supported by MaX (www.max-centre.eu)<br clear="none">users mailing list <a shape="rect" ymailto="mailto:users@lists.quantum-espresso.org" href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a><br clear="none"><a shape="rect" href="https://lists.quantum-espresso.org/mailman/listinfo/users" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a><div class="yqt3727004091" id="yqtfd99702"><br clear="none"></div></div></div>
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