Dear CP2K Users and Developers, I am trying to model Ga and O adatom diffusion barriers on substrates like diamond and sapphire using CP2K (periodic DFT + NEB), and I have a few questions regarding best practices: 1. k-point Sampling: Some CP2K publications seem to use only Gamma-point, even for periodic systems. In contrast, codes like Quantum ESPRESSO require k-point convergence for accuracy. <ul> <li> Is k-point convergence generally not needed in CP2K. </li> <li> When should one use explicit k-point grids in CP2K. </li> </ul> 2. Slab Model Passivation: In plane-wave codes, bottom surface passivation (e.g., with hydrogen) is common in slab models to avoid spurious states. But I rarely see this in CP2K-based surface studies. <ul> <li> Is bottom-layer passivation not necessary in CP2K.</li> </ul> 3. Convergence Parameters: Is optimizing CUTOFF and REL_CUTOFF typically sufficient for accurate periodic DFT and NEB calculations in CP2K. <ul> <li> Are other parameters like basis sets (as here we use Gaussian instead of plane wave) or grid levels also important to converge. </li> <li> Any recommended references for CP2K convergence strategies. </li> </ul> Any guidance or pointers to best practices would be greatly appreciated. Best Regards,Usman -- 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/c5f6a0ac-b000-4a21-a82a-6bd8f2bd7815n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/c5f6a0ac-b000-4a21-a82a-6bd8f2bd7815n%40googlegroups.com</a>.