Dear developers, Recently, I used CP2K to calculate the binding energy of SO2 in Co-MOF-74-Co material, the binding energy was defined as E=E(ab)-E(a)-E(b), where the E(ab), E(a) and E(b) are the energy of SO2-MOF-74 unit, MOF-74, SO2, respectively. However, the calculated binding energy is a positive value, rather than a negative value if calculated rightly. On the one hand, I have tested the ground spin state (simple spin multiplicity=1 and spin polarized state) before performing calculation, and the results shows that the spin polarized state is the true ground state with lower energy, and the spin population over different Co atoms seems right. Finally, the TZVP-MOLOPT-GTH basis set is used for energy calculation. On the other hand, I have also tested the binding energy with a simple spin multiplicity equal to 1, but the result also shows a positive value, so I don’t know what is going on my calculations, could you help me to fix this problem? The related input files have been attached below. Note: the **-uks.inp means spin ploarized calculatoin -- 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/2fc2cb65-1605-417a-8909-25622f94e1dan%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/2fc2cb65-1605-417a-8909-25622f94e1dan%40googlegroups.com</a>.