I managed to find a way to print the HOMO - LUMO gap from the pdos. The only problem now is that for some reason I get a band gap of 85 eV for silicon when using a hybrid functional.<br /><br /><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Tuesday, September 10, 2024 at 1:54:25 PM UTC-5 Thomas Kasel wrote:<br/></div><blockquote class="gmail_quote" style="margin: 0 0 0 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">Thanks to your suggestions I managed to get the SCF to converge for PBE based upon playing with the mixing. The only problem is now that CP2K is not printing the HOMO-LUMO gap. Is there a setting I can specify to force print the gap?<div><br></div><div>Regards,</div><div>Tom<br><br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Tuesday, September 10, 2024 at 4:45:21 AM UTC-5 Jürg Hutter wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi
<br>
<br>For silicon: if you are using the unit cell (with 2 atoms) you need a large number of k-points.
<br>In this case SCF needs diagonalization and an appropriate mixing scheme. I would also add smearing
<br>of occupation numbers. If you have this working, you can start investigating basis sets for convergence.
<br>
<br>For graphene: The problem is the Dirac cone at the K special point. Selecting a matching cell and k-point
<br>sampling is mandatory to get correct results. There is ample literature addressing this problem.
<br>
<br>regards
<br>JH
<br>
<br>________________________________________
<br>From: <a rel="nofollow">cp...@googlegroups.com</a> <<a rel="nofollow">cp...@googlegroups.com</a>> on behalf of Thomas Kasel <<a rel="nofollow">tomk...@gmail.com</a>>
<br>Sent: Monday, September 9, 2024 10:50 PM
<br>To: cp2k
<br>Subject: [CP2K:20677] Incorrect Band gaps from simple calculations
<br>
<br>Hello All,
<br>
<br>As a test I am trying to accurately (relatively) reproduce the band gaps of silicon and graphene structures using PBE. I have however, run into an issue where graphene gives a band gap of 1.2 eV while silicon gives a band gap of 0.18 eV, the exact opposite of what one would expect. I would like to ask what it is I am doing wrong in my calculations. Attached is a zip file containing all my input files including basis set and pseudopotentials.
<br>
<br>Additionally, I cannot seem to get the SCF to converge unless I specify:
<br>
<br>&OT
<br> PRECONDITIONER FULL_ALL
<br> MINIMIZER CG
<br>&END OT
<br>
<br>Why is this setting so critical to SCF convergence in these cases?
<br>
<br>Cheers and thanks in advance,
<br>Tom
<br>
<br>--
<br>You received this message because you are subscribed to the Google Groups "cp2k" group.
<br>To unsubscribe from this group and stop receiving emails from it, send an email to <a rel="nofollow">cp2k+uns...@googlegroups.com</a><mailto:<a rel="nofollow">cp2k+uns...@googlegroups.com</a>>.
<br>To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/cf2a1d8d-c40c-4da4-9857-38cd2b7e7e91n%40googlegroups.com" rel="nofollow" target="_blank" data-saferedirecturl="https://www.google.com/url?hl=en&q=https://groups.google.com/d/msgid/cp2k/cf2a1d8d-c40c-4da4-9857-38cd2b7e7e91n%2540googlegroups.com&source=gmail&ust=1726153312785000&usg=AOvVaw2WrEK9Tl0nfvrSAe-ONpuG">https://groups.google.com/d/msgid/cp2k/cf2a1d8d-c40c-4da4-9857-38cd2b7e7e91n%40googlegroups.com</a><<a href="https://groups.google.com/d/msgid/cp2k/cf2a1d8d-c40c-4da4-9857-38cd2b7e7e91n%40googlegroups.com?utm_medium=email&utm_source=footer" rel="nofollow" target="_blank" data-saferedirecturl="https://www.google.com/url?hl=en&q=https://groups.google.com/d/msgid/cp2k/cf2a1d8d-c40c-4da4-9857-38cd2b7e7e91n%2540googlegroups.com?utm_medium%3Demail%26utm_source%3Dfooter&source=gmail&ust=1726153312785000&usg=AOvVaw0kaIrVSa3GS5WWyF7f_J96">https://groups.google.com/d/msgid/cp2k/cf2a1d8d-c40c-4da4-9857-38cd2b7e7e91n%40googlegroups.com?utm_medium=email&utm_source=footer</a>>.
<br></blockquote></div></blockquote></div>

<p></p>

-- <br />
You received this message because you are subscribed to the Google Groups "cp2k" group.<br />
To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>.<br />
To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/519f408c-fb0c-4c48-9a70-a36fbdc02f23n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/519f408c-fb0c-4c48-9a70-a36fbdc02f23n%40googlegroups.com</a>.<br />