<div dir="ltr">Just to be 100% clear, are you saying that for the &POISSON section which deals with the electrostatic potential, that I select PERIODIC XY?</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Mar 2, 2021 at 4:55 PM Lucas Lodeiro <<a href="mailto:eluni...@gmail.com">eluni...@gmail.com</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 dir="ltr">Just a comment, see your electrostatic potential profile. You are using a periodical slab picture, then when you add a polar molecule, there is not a flat potential into the vacuum, in that case, disable the periodicity in this direction or add an electrostatic field to correct it.<div>Also, to check the convergence of your quantities with respect to your model, you could explore bigger slabs than 6 layers.</div><div><br></div><div>Regards - Lucas Lodeiro</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">El mar, 2 mar 2021 a las 6:37, ASSIDUO Network (<<a href="mailto:lenardc...@gmail.com" target="_blank">lenardc...@gmail.com</a>>) escribió:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Thank you for the quick response.<div><br></div><div>I understand what you are saying and it makes total sense to me. Thank you for clarifying.<br><br>The 3x3x1 was just to test how my final adsorption energy changes when I change various settings, including alpha, beta, kpoints and cutoff. I got similar results to the the 5x5x1 case, however the 5x5x1 result was more accurate compared to the ltierature.<br><br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Tuesday, March 2, 2021 at 11:33:40 AM UTC+2 <a href="mailto:fa...@gmail.com" target="_blank">fa...@gmail.com</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 Lenard,</div><div><br></div><div>Yes, you have correctly answered your question. For metals you need a quite good sampling of the brillouin zone. Therefore a gamma-point calculation of a 5x5 angstrom unit cell is expected to yield unreasonable results. <br></div><div>The fact that you managed to get a good structure with a cutoff of 300 is probably due to a coincidental error cancelling. But as soon as you alter the configuration by adding a CO the error cancelling does not work anymore and the structure becomes unreasonable again.<br></div><div><br></div><div>You should make sure that your quantity of interest is converged w.r.t the size of the k-point grid. 3x3x1still seems small to me, but maybe its already enough for you.</div><div><br></div><div>Cheers,</div><div>Fabian<br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Tuesday, 2 March 2021 at 06:42:45 UTC+1 ASSIDUO Network 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">Hi there everyone, I am currently trying to geometry optimize a stack of Au (111) 2x2 surfaces, specifically by fixing the bottom 3 surfaces and relaxing the top 3.<div><br></div><div>Unfortunately, the top surfaces completely mess up and the final structure looks bad. When I turn KPOINTS on (3x3x1 or 5x5x1), it no longer happens.</div><div>Finally, when I lower the cutoff to 300, but I leave KPOINTS off, I get a good optimized geometry, but when I try to perform a CO adsorption with that optimized structure, it severely deforms as well.</div><div><br></div><div>Does anyone have a solution to my problem, particularly one that doesn't change the ELECTRONIC_TEMPERATURE, KPOINTS or CUTOFF. Is it the need for KPOINTS in a small structure like this that messes up the results?<br><br>I have attached all my relevant files.<br><br>Kind regards,<br>Lenard</div></blockquote></div></blockquote></div>
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