<div dir="ltr"><div dir="auto">Hi,</div><div dir="auto"><br></div><div dir="auto">I’m gonna jump in if you don’t mind. I am trying to do cell optimization of fcc copper. I used k points and got 3.65A which is different from the 3.62 that was expected. I was wondering for your latter option (using a large simulation cell) , would Run CELL_OPT or GEO_OPT?</div></div><div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, May 16, 2021 at 8:46 PM Krack Matthias (PSI) <<a href="mailto:matthi...@psi.ch" target="_blank">matthi...@psi.ch</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 lang="EN-US"> <div> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Hi Yike<u></u><u></u></span></p> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Your simulation cell is small and you use no k point sampling. Either you use k point sampling or you enlarge your simulation cell to at least a cell edge length of 12 A in each direction. I suggest the latter option for CP2K. Furthermore, you could reduce EPS_DEFAULT to 1.0E-12 and increase REL_CUTOFF to 60.<u></u><u></u></span></p> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">HTH<u></u><u></u></span></p> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Matthias<u></u><u></u></span></p></div></div><div lang="EN-US"><div> <p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p> <div style="border-top:none;border-right:none;border-bottom:none;border-left:1.5pt solid blue;padding:0cm 0cm 0cm 4pt"> <div> <div style="border-right:none;border-bottom:none;border-left:none;border-top:1pt solid rgb(225,225,225);padding:3pt 0cm 0cm"> <p class="MsoNormal"><b><span lang="DE" style="font-size:11pt;font-family:Calibri,sans-serif">Von:</span></b><span lang="DE" style="font-size:11pt;font-family:Calibri,sans-serif"> <a href="mailto:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a> <<a href="mailto:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a>> <b>Im Auftrag von </b>Yike Huang<br> <b>Gesendet:</b> Sonntag, 16. Mai 2021 18:23<br> <b>An:</b> cp2k <<a href="mailto:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a>><br> <b>Betreff:</b> [CP2K:15385] Unreasonable CELL_OPT result obtained for TiO2<u></u><u></u></span></p> </div> </div> <p class="MsoNormal"><u></u> <u></u></p> <p class="MsoNormal">Hello, cp2k developers and users,<u></u><u></u></p> <div> <p class="MsoNormal"><u></u> <u></u></p> <div> <p class="MsoNormal">I try to optimize primitive cell of rutile TiO2 by running CELL_OPT calculation at PBE+U(presently set to 0 eV)/DZVP level, but I find cell parameters deviate from experimental values quite quickly during calculation.<u></u><u></u></p> </div> <div> <p class="MsoNormal">I have tried changing STRESS_TENSOR to both NUMERICAL and ANALYTICAL but it does not help, I also think it may be not the reason why I get this kind of strange result.<u></u><u></u></p> </div> <div> <p class="MsoNormal">I attach my input script and CIF file below, are there any parameters in input script I forget?<u></u><u></u></p> </div> <div> <p class="MsoNormal">In addition, anatase TiO2 CELL_OPT task also has such problem, but I remember that primitive cell of Co3O4 can be successfully optimized.<u></u><u></u></p> </div> <div> <p class="MsoNormal"><u></u> <u></u></p> </div> <div> <p class="MsoNormal">Thanks in advance.<u></u><u></u></p> </div> </div> <div> <p class="MsoNormal"><u></u> <u></u></p> </div> <div> <p class="MsoNormal">Yike Huang<u></u><u></u></p> </div> <p class="MsoNormal">-- <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:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a>.<br> To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/11f85e5a-b3f6-45b2-b164-11f12644f358n%40googlegroups.com?utm_medium=email&utm_source=footer" target="_blank"> https://groups.google.com/d/msgid/cp2k/11f85e5a-b3f6-45b2-b164-11f12644f358n%40googlegroups.com</a>.<u></u><u></u></p> </div> </div></div><div lang="EN-US"><div></div> </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:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a>.<br> To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/b6c6bd92f59a4a41b1155ab00ac8bfc4%40psi.ch?utm_medium=email&utm_source=footer" target="_blank">https://groups.google.com/d/msgid/cp2k/b6c6bd92f59a4a41b1155ab00ac8bfc4%40psi.ch</a>.<br> </blockquote></div></div>