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On Friday, 16 September, 2022 at 09:43:22 am GMT+1, Giuseppe Mattioli <giuseppe.mattioli@ism.cnr.it> wrote:
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<div><br>You should use gamma-only (which is less greedy for memory and faster <br>than any other option) when<br><br>1) your system isn't really periodic and does not show bandlike <br>dispersion in k (e.g., an isolated molecule or a cluster in a large <br>periodic box).<br><br>2) your system is not a unit cell and it is so large that the band <br>structure in the (tiny) Brillouin zone is practically all refolded <br>into gamma. In this case you should usually check the convergence of <br>total energy/forces with respect to k points to stay on the safe side.<br><br>HTH<br>Giuseppe<br><br>Quoting naval singh via users <<a ymailto="mailto:users@lists.quantum-espresso.org" href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a>>:<br><br>> Dear all,i have been using quantum espresso for some time and using <br>> k points i came across a paper where a researcher used gamma points <br>> calculation owing to the size of the cell, i wanted to know when <br>> should one use the gamma k points caclculations <br><br><br><br>GIUSEPPE MATTIOLI<br>CNR - ISTITUTO DI STRUTTURA DELLA MATERIA<br>Via Salaria Km 29,300 - C.P. 10<br>I-00015 - Monterotondo Scalo (RM)<br>Mob (*preferred*) +39 373 7305625<br>Tel + 39 06 90672342 - Fax +39 06 90672316<br>E-mail: <<a ymailto="mailto:giuseppe.mattioli@ism.cnr.it" href="mailto:giuseppe.mattioli@ism.cnr.it">giuseppe.mattioli@ism.cnr.it</a>><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 <a ymailto="mailto:users@lists.quantum-espresso.org" href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a><br><a href="https://lists.quantum-espresso.org/mailman/listinfo/users" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></div>
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