<div><blockquote style="margin: 0px 0px 0px 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> The system is a RuO₂ (110) surface modeled with three layers — the bottom layer is fixed during the calculation, while the top two are relaxed. I'm using diagonalization for the SCF method. For the clean surface (*) and the *O intermediate, SCF converges without any issues. However, once I introduce H-containing intermediates like *OH and *OOH, the SCF becomes extremely slow and often oscillates without converging at all. I've tried increasing MAX_SCF to 500, set Alpha to 0.1, and switched the optimizer to CG, but the results are still not ideal. Since the system is metallic, I didn't use the OT method. </blockquote><div> Hello, First of all, no matter whether you are using OT or not, you certainly need OUTER_SCF. For example: &SCF MAX_SCF 20 EPS_SCF 1E-6 &OUTER_SCF T EPS_SCF 1E-6 MAX_SCF 128 &END OUTER_SCF &END Also, have you actually tried using OT with your system? Tweaking its options like ENERGY_GAP might be helpful. And if it converges, you can restart without OT from resulting wfn file. </div></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 visit <a href="https://groups.google.com/d/msgid/cp2k/74209450-8353-4c1d-8730-1f9516393887n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/74209450-8353-4c1d-8730-1f9516393887n%40googlegroups.com</a>.