Dear Rajorshi,<div> </div><div>The original SCAN functional is known to be very sensitive to the integration grid used during calculation. </div><div>An easy fix would be to switch to r2SCAN (acs.jpclett.0c02405) instead: </div><div> </div><div> &XC &XC_FUNCTIONAL &MGGA_X_R2SCAN &END &MGGA_C_R2SCAN &END &END &END XC</div><div> </div><div>Typically, the cutoff should be converged at 1200Ry with SCAN.</div><div> </div><div>Kind regards,</div><div>Fabian</div><div class="gmail_quote"><div dir="auto" class="gmail_attr">Rajorshi Chattopadhyay schrieb am Freitag, 17. März 2023 um 00:11:52 UTC+1: </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">Dear all,<div> </div><div>I am trying to do cutoff convergence with the SCAN functional in a aqueous H2O-H2SO4 system. I need an energy convergence of 10**-6 Ha or lower. However, I find that even at a cutoff of 4000Ry (REL_CUTOFF:60), energy convergence is only 10**-4 Ha. The input script is as follows:</div><div> </div><div>&GLOBAL PROJECT Sulphate_amb_dens RUN_TYPE ENERGY_FORCE PRINT_LEVEL MEDIUM&END GLOBAL&FORCE_EVAL&DFT MULTIPLICITY 1 BASIS_SET_FILE_NAME ./BASIS_MOLOPT POTENTIAL_FILE_NAME ./SCAN_POTENTIALS &MGRID CUTOFF 3800 REL_CUTOFF 60 NGRIDS 4 &END MGRID &SCF SCF_GUESS ATOMIC MAX_SCF 3000 EPS_SCF 1.00000000E-007 &OT MINIMIZER DIIS PRECONDITIONER FULL_SINGLE_INVERSE &END OT &END SCF &XC &XC_FUNCTIONAL &LIBXC FUNCTIONAL MGGA_X_SCAN &END LIBXC &LIBXC FUNCTIONAL MGGA_C_SCAN &END LIBXC &END XC_FUNCTIONAL &END XC &END DFT &SUBSYS &TOPOLOGY &CENTER_COORDINATES TRUE &END CENTER_COORDINATES &END TOPOLOGY &CELL ABC 12.32 12.32 12.32 PERIODIC XYZ &END CELL &COORD @include ../coord_eql &END COORD &KIND H BASIS_SET DZVP-MOLOPT-SR-GTH POTENTIAL GTH-SCAN-q1 &END &KIND O BASIS_SET DZVP-MOLOPT-SR-GTH POTENTIAL GTH-SCAN-q6 &END &KIND S BASIS_SET DZVP-MOLOPT-GTH POTENTIAL GTH-SCAN-q6 &END &END SUBSYS &END FORCE_EVAL I use the pseudopotentials provided by Dr. Joerg Hutter in his github.</div><div> </div><div>Am I missing something in the input script ? Is it possible to achieve such tight energy convergences using SCAN the functional?</div><div> </div><div>I thank you in advance for your help/suggestions. <div> </div>-- <div dir="ltr" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div>With Regards,</div><div>Rajorshi Chattopadhyay,</div><div>PhD Researcher in Mineralogy/Crystallography,</div><div>Institut für Geologie und Mineralogie,</div><div>Universität zu Köln, Germany </div><div style="font-size:small"> </div><div style="font-size:small"></div></div></div></div></div></div></div> </blockquote></div> -- You received this message because you are subscribed to the Google Groups "cp2k" group. 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>. To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/a68b39f8-10cc-4a1f-a6a4-a3aa8c0893ffn%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/a68b39f8-10cc-4a1f-a6a4-a3aa8c0893ffn%40googlegroups.com</a>.