However, the sigma values for some metal atoms tend to be overestimated, preventing guest molecules from approaching the OMS closely enough. Consequently, the interaction between the MOF and the guest molecule is underestimated. Unlike H2O, CO2 cannot generate sufficient electrostatic potential to counterbalance this underestimation in interaction energy. For FECWOB01, the Qst values for both CO2 and H2O are underestimated, though the trend of CO2 Qst being higher than H2O Qst remained consistent. FECWOB01 contains an azole linker, and since the electronegativity of azoles varies with the nitrogen content, the force field parameters of nitrogen require careful consideration. For example, a study on ZIF-8, which contains imidazole as an organic linker, derived a tailored force field by using nitrogen parameters from Generalized Amber Force Field (GAFF). In this case, the epsilon value was set at 85.5 K, which is 2.5 times larger than that in UFF, while the sigma value remained nearly identical. Similarly, applying a larger epsilon for nitrogen in azoles would likely increase the interaction strength for both CO2 and H2O.