Dear All, Here, I also attach the test results with different <span style="color: rgb(15, 15, 15); font-family: Söhne, ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, Cantarell, "Noto Sans", sans-serif, "Helvetica Neue", Arial, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"; font-size: 16px; white-space-collapse: preserve;">REL_CUTOFF and CUTOFF. This indicates that the cutoff I used is fully converged. Could anyone tell me the possible reason for the sharp decrease in energy in the EOS curves.<span style="color: rgb(15, 15, 15); font-family: Söhne, ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, Cantarell, "Noto Sans", sans-serif, "Helvetica Neue", Arial, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"; font-size: 16px; white-space-collapse: preserve;"> Thanks. Best regards, Kejiang <img alt="cutoffs.png" width="579px" height="397px" src="cid:d84f9297-2c46-49eb-84b4-67fea5843552" /> <div class="gmail_quote"><div dir="auto" class="gmail_attr">On Monday, November 20, 2023 at 9:00:11 AM UTC+8 Kejiang Li wrote: </div><blockquote class="gmail_quote" style="margin: 0 0 0 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div>Dear CP2K community, I am calculating the EOS for FeO with a 2*2*2 supercell. But there is always a significant discontinuity (sharp decrease) in the range of 4.3-4.4 angstrom lattice constant in the EOS curves, as shown in the figures below. I have done the following tests: - the convergence of the energy with different cutoffs; - using different functionals, including PBE, HSE, and SCAN; -including HSE with different HF fractions; -using different magnetization and +U settings. However, all the tests produce similar results with an apparent discontinuity (4.3-4.3 A) . This discontinuity is not observed in the Quantum Espresso results conducted by myself and in the results of literature that generally used VASP. I believe that the CP2K program might cause this problem. Can you give me more suggestions on how to do further tests? Here, I also attached one sample code I used during my tests. Thanks a lot. Best regards, Kejiang The University of Science and Technology Beijing </div><img alt="cp2k_functionals.jpg" width="534px" height="336px" src="https://groups.google.com/group/cp2k/attach/9606971979e0d/cp2k_functionals.jpg?part=0.2&view=1"> <div><img alt="cp2k_mag_u.jpg" width="534px" height="381px" src="https://groups.google.com/group/cp2k/attach/9606971979e0d/cp2k_mag_u.jpg?part=0.4&view=1"><img alt="cp2k_mag_u2.jpg" width="534px" height="346px" src="https://groups.google.com/group/cp2k/attach/9606971979e0d/cp2k_mag_u2.jpg?part=0.3&view=1"> </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/29c001b9-6e62-4f63-80a4-cd7f39272edcn%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/29c001b9-6e62-4f63-80a4-cd7f39272edcn%40googlegroups.com</a>.