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Dear Prasenjit,</div>
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You can restart from where you are now. The changes should not be dramatic. </div>
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Best,</div>
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Iurii</div>
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Dr. Iurii TIMROV</div>
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Tenure-track scientist</div>
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Laboratory for Materials Simulations (LMS)</div>
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Paul Scherrer Institut (PSI)</div>
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CH-5232 Villigen, Switzerland</div>
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+41 56 310 62 14</div>
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<a data-linkindex="0" data-auth="NotApplicable" rel="noopener noreferrer" target="_blank" href="https://www.psi.ch/en/lms/people/iurii-timrov">https://www.psi.ch/en/lms/people/iurii-timrov</a></div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Prasenjit Ghosh <pghosh@iiserpune.ac.in><br>
<b>Sent:</b> Wednesday, August 6, 2025 14:32<br>
<b>To:</b> Timrov Iurii <iurii.timrov@psi.ch><br>
<b>Cc:</b> users@lists.quantum-espresso.org <users@lists.quantum-espresso.org><br>
<b>Subject:</b> Re: [QE-users] Speed up force calculations</font>
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<div>Dear Iurii,</div>
<div>I am using 'ortho-atomic' projectors.</div>
<div>If I shift to 'atomic', I need to recalculate everything, right?</div>
<div>Prasenjit</div>
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<div dir="ltr" class="x_gmail_attr">On Wed, Aug 6, 2025 at 6:01 PM Timrov Iurii <<a href="mailto:iurii.timrov@psi.ch">iurii.timrov@psi.ch</a>> wrote:<br>
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Dear Prasenjit,</div>
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Are you using 'atomic' or 'ortho-atomic' projectors in PBE+U? The former is much faster for computing Hubbard forces and stresses, but less accurate (from our experience).</div>
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HTH</div>
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Iurii</div>
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Dr. Iurii TIMROV</div>
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Tenure-track scientist</div>
<div style="font-family:Cambria,Georgia,serif; font-size:12pt; color:rgb(102,102,102)">
Laboratory for Materials Simulations (LMS)</div>
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Paul Scherrer Institut (PSI)</div>
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CH-5232 Villigen, Switzerland</div>
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+41 56 310 62 14</div>
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<a rel="noopener noreferrer" href="https://www.psi.ch/en/lms/people/iurii-timrov" target="_blank">https://www.psi.ch/en/lms/people/iurii-timrov</a></div>
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<div id="x_m_365804935407277845divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> users <<a href="mailto:users-bounces@lists.quantum-espresso.org" target="_blank">users-bounces@lists.quantum-espresso.org</a>>
on behalf of Prasenjit Ghosh via users <<a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a>><br>
<b>Sent:</b> Wednesday, August 6, 2025 14:05<br>
<b>To:</b> <a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a> <<a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a>><br>
<b>Subject:</b> [QE-users] Speed up force calculations</font>
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<div>Dear all,</div>
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<div>I am performing a "relax" calculation with QE 7.3.1 using PBE+U.</div>
<div>The system has 576 atoms (2920 electrons).</div>
<div>I am running this calculation on our supercomputer using 6 nodes (288 cores). Each node has two Intel(R) Xeon(R) Platinum 8268 CPU @ 2.90GHz and 192 GB RAM.</div>
<div>QE has been compiled with intel compilers.</div>
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<div>While a scf cycle completes in a reasonable time frame (~1 hour), force calculation at the end of each scf cycle takes about 5.5 hours.</div>
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<div>I was wondering if there is any way, without increasing the number of cores, to speed up the force calculations.</div>
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<div>Waiting for your suggestions.</div>
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<div>With regards,</div>
<div>Prasenjit Ghosh</div>
<div>IISER Pune</div>
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