Sometimes the optimal values are not around well-identified values but are contained within larger domains with threshold values separating them. For instance, the difference between the LCD and the average pore size "delta_pore" has a threshold value around 0.3 Å below which the contribution for the most selective structures (blue) is negative (see Figure ); even though there is no clear correlations, we can at least find a threshold value (about 0.23) below which there is higher probability of having a high ambient-pressure selectivity. There is the same type of domain splits for the average of krypton interaction energies distribution "mean_grid_krypton" (at around 15), the Boltzmann weighted xenon interaction energies distribution "enthalpy_std_xenon" (at around 2.5), the difference of exchange entropic term between the ambient temperature "delta_TS0_298_900" (at around