Thanks for your advice, Lucas. I have tried decrease EPS_SCF to 3.0E-7, and the force did not change compared to EPS_SCF=5.0E-6 at the same cutoff. I will try a lower EPS_SCF and take a look of XC_GRID.<br> <div class="gmail_quote"><div dir="auto" class="gmail_attr">在2021年2月16日星期二 UTC+8 下午12:08:05<Lucas Lodeiro> 写道：<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 dir="ltr">Hi Hedley,<div><br></div><div>Typically forces are more difficult to converge. Forces are more sensitive to convergence parameters, and are affected by "noise" in the derivation. Have you tried to decrease the EPS_SCF? Maybe 5E-6 is not sufficient to ensure a free noise force... 1E-7 or 1E-8 could be useful to smooth the force profile respect to cutoff. And the XC_GRID subsection could be useful.</div><div><br></div><div>Regards - Lucas Lodeiro</div></div><br><div class="gmail_quote"></div><div class="gmail_quote"><div dir="ltr" class="gmail_attr">El lun, 15 feb 2021 a las 23:57, Hedley Dong (<<a href data-email-masked rel="nofollow">dm...@gmail.com</a>>) escribió:<br></div></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><img alt="1.PNG" width="1221px" height="376px" src="https://groups.google.com/group/cp2k/attach/52f3c8b1c4824/1.PNG?part=0.1&view=1"><br><br><div class="gmail_quote"><div dir="auto" class="gmail_attr">在2021年2月16日星期二 UTC+8 上午10:44:48<Hedley Dong> 写道：<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>&GLOBAL</div><div>PROJECT DPGEN</div><div>&END GLOBAL</div><div>&FORCE_EVAL</div><div>METHOD QS</div><div>STRESS_TENSOR ANALYTICAL</div><div>&DFT</div><div>BASIS_SET_FILE_NAME BASIS_MOLOPT</div><div>POTENTIAL_FILE_NAME GTH_POTENTIALS</div><div>CHARGE 0</div><div>UKS T</div><div>MULTIPLICITY 1</div><div>&MGRID</div><div>CUTOFF 350</div><div>REL_CUTOFF 50</div><div>NGRIDS 4</div><div>&END MGRID</div><div>&QS</div><div>EPS_DEFAULT 1.0E-12</div><div>&END QS</div><div>&SCF</div><div>SCF_GUESS ATOMIC</div><div>EPS_SCF 5.0E-6</div><div>MAX_SCF 300</div><div>&OT</div><div>PRECONDITIONER FULL_SINGLE_INVERSE</div><div>MINIMIZER DIIS</div><div>&END OT</div><div>&OUTER_SCF ON</div><div>MAX_SCF 4</div><div>&END OUTER_SCF</div><div>&END SCF</div><div>&XC</div><div>&XC_FUNCTIONAL PBE</div><div>&END XC_FUNCTIONAL</div><div>&vdw_POTENTIAL</div><div>DISPERSION_FUNCTIONAL PAIR_POTENTIAL</div><div>&PAIR_POTENTIAL</div><div>TYPE DFTD3</div><div>PARAMETER_FILE_NAME dftd3.dat</div><div>REFERENCE_FUNCTIONAL PBE</div><div>R_CUTOFF 15.</div><div>&END PAIR_POTENTIAL</div><div>&END vdw_POTENTIAL</div><div>&END XC</div><div>&END DFT</div><div>&SUBSYS</div><div>&CELL</div><div>A 7.552 0. 0. </div><div>B 0. 7.552 0. </div><div>C 0. 0. 18.972</div><div>&END CELL</div><div>&COORD</div><div>@include <a href="http://coord.xyz" rel="nofollow" target="_blank" data-saferedirecturl="https://www.google.com/url?hl=zh-CN&q=http://coord.xyz&source=gmail&ust=1613536475537000&usg=AFQjCNEEULulkHUxADkGfMO8Zzo-KGdzfg">coord.xyz</a></div><div>&END COORD</div><div>&KIND O</div><div>BASIS_SET DZVP-MOLOPT-SR-GTH</div><div>POTENTIAL GTH-PBE-q6</div><div>&END</div><div>&KIND Ti</div><div>POTENTIAL GTH-PBE-q12</div><div>BASIS_SET DZVP-MOLOPT-SR-GTH</div><div>&DFT_PLUS_U</div><div>EPS_U_RAMPING 1.0E-3</div><div>U_RAMPING [eV] 1</div><div>L 2</div><div>U_MINUS_J [eV] 5</div><div>&END DFT_PLUS_U</div><div>&END</div><div>&END SUBSYS</div><div>&PRINT</div><div>&FORCES ON</div><div>&END FORCES</div><div>&STRESS_TENSOR ON</div><div>&END STRESS_TENSOR</div><div>&END PRINT</div><div>&END FORCE_EVAL</div><div><br></div></blockquote></div> <p></p></blockquote></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> -- <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 data-email-masked rel="nofollow">cp...@googlegroups.com</a>.<br> To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/8485d638-b1d6-4586-b761-fe0193384ac4n%40googlegroups.com?utm_medium=email&utm_source=footer" target="_blank" rel="nofollow" data-saferedirecturl="https://www.google.com/url?hl=zh-CN&q=https://groups.google.com/d/msgid/cp2k/8485d638-b1d6-4586-b761-fe0193384ac4n%2540googlegroups.com?utm_medium%3Demail%26utm_source%3Dfooter&source=gmail&ust=1613536475537000&usg=AFQjCNHBhqMy40yYCuWrQmd29G0MZsIgTg">https://groups.google.com/d/msgid/cp2k/8485d638-b1d6-4586-b761-fe0193384ac4n%40googlegroups.com</a>.<br> </blockquote></div> </blockquote></div>