We explore two approaches to determine the U parameter for the data set consisting of 72 MOF/adsorbate systems. Firstly, taking into account the specific characteristics of the SBU composition, we individually fit the U parameter for each SBU/gas-molecule system. We refer to this customized U value as the SBU-specific U, or USBU. Secondly, focusing solely on the chemistry between the metal atom and the gas molecule, we fit the U parameter for a group of SBUs that share the same metal/gas-molecule pair. In this case, we determine the U parameter by minimizing the MAD of each grouping. We refer to this calibrated U value as the metal-specific U, or Umetal (Supporting Information Table ). Even though we refer to this as the metal-specific U, it also is unique for each adsorbate (i.e., CO2, N2, or O2).