<div>Hi,</div><div><br></div><div>> Could you send a break down of the energies for the LiF molecule for
<br>the two codes? <br></div><div><br></div><div>I just realized I used to small a cell in this case. I just reran the calculations for the LiF molecule and now CP2K and DFTB+ results match very well. Apologies for the confusion. This means I have only found the problem in periodic systems, which might provide a clue... Please let me know if you would like to see any other data.</div><div><br></div><div>> do you have any reasons to expect that these methods must
yield similar results? They are different and both are not so
precise for the systems with complicated electronic effects</div><div><br></div><div>My understanding is that they are the same method (GFN1-xTB) with at most small differences in default parameters, and I expected at least qualitatively the same results (on par with using say, PBE, with two different DFT codes). Maybe I've missed something important here?</div><div><br></div><div>Kind regards,</div><div>Magnus<br></div><div><br></div><br><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Monday, September 5, 2022 at 11:47:06 AM UTC+2 anton.s.l...@gmail.com 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;">
<div>
<p>Dear Magnus,</p>
<p>but do you have any reasons to expect that these methods must
yield similar results? They are different and both are not so
precise for the systems with complicated electronic effects.</p>
<p>Yours,</p>
<p>Anton<br>
</p>
<div>01.09.2022 12:48, Magnus Rahm пише:<br>
</div>
<blockquote type="cite"></blockquote></div><div><blockquote type="cite">
Dear all,<br>
<br>
I want to use CP2K (version 8.2, trying to get a more recent
version compiled) together with xTB for a crystal containing Li
and O. I get strange results already for a simple LiO2 crystal:<br>
<br>
* There is a very large discrepancy compared to DFTB+ (version
22.1).<br>
* Mulliken charges tend to be large, meaning that
CHECK_ATOMIC_CHARGES stops the SCF. If I turn it off, the system
tends to converge systematically to values just outside the
"chemical range". Mulliken charges obtained by DFTB+ are
significantly smaller (and within "chemical range").<br>
* The energy-volume curve looks strange and very different from
DFTB+.<br>
<br>
I have tried converging with respect to system size and the EWALD
/ ALPHA and GMAX parameters, but they have only a marginal impact.
I have tried similar calculations for a number of periodic
systems. Sometimes I get agreement, sometimes not. I also tried
calculations for CO and NO molecules which agree perfectly between
CP2K and DFTB+, whereas an artificial LiF molecule does not.<br>
<br>
A perhaps related issue was reported in
<a href="https://groups.google.com/g/cp2k/c/oFwgGcQuySs" target="_blank" rel="nofollow" data-saferedirecturl="https://www.google.com/url?hl=en&q=https://groups.google.com/g/cp2k/c/oFwgGcQuySs&source=gmail&ust=1662457803026000&usg=AOvVaw0Mv5LY7eXhDKcWs6-N9iTN">https://groups.google.com/g/cp2k/c/oFwgGcQuySs</a> but the solutions
suggested there did not solve my problem.<br>
<br>
I attach input scripts for CP2K and DFTB+, as well as a figure
showing the E-V curve for LiO2 obtained with CP2K and DFTB+. I'm
new to CP2K, DFTB+ and xTB so I suspect I have made some simple
mistake, and any advice is appreciated.<br>
<br>
Kind regards,<br>
Magnus Rahm<br>
<br>
<br>
<br>
<br>
<br></blockquote></div><div><blockquote type="cite">
-- <br>
You received this message because you are subscribed to the Google
Groups "cp2k" group.<br></blockquote></div><div><blockquote type="cite">
To unsubscribe from this group and stop receiving emails from it,
send an email to <a href data-email-masked 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/2b7a001c-6e70-4e27-bb1d-cd6c1f4765f9n%40googlegroups.com?utm_medium=email&utm_source=footer" target="_blank" rel="nofollow" data-saferedirecturl="https://www.google.com/url?hl=en&q=https://groups.google.com/d/msgid/cp2k/2b7a001c-6e70-4e27-bb1d-cd6c1f4765f9n%2540googlegroups.com?utm_medium%3Demail%26utm_source%3Dfooter&source=gmail&ust=1662457803026000&usg=AOvVaw0DgNbm3koGox13GeOnrqAk">https://groups.google.com/d/msgid/cp2k/2b7a001c-6e70-4e27-bb1d-cd6c1f4765f9n%40googlegroups.com</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/4a80c6bd-6071-43fb-a996-b179d1767dc9n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/4a80c6bd-6071-43fb-a996-b179d1767dc9n%40googlegroups.com</a>.<br />