Using the quasi-RRHO approximation, we can estimate the binding free energy for model clusters considered in our combinatorial search (Table ). It is important to note the computational challenge in the precise calculations of Gibbs free energies, as they include an entropic term that can be significantly impacted by the anharmonicity of nuclear vibrations. Thus, the enthalpy values provided in Table are more accurate than the corresponding Gibbs free energies. Despite these challenges, the computed ΔG values can still serve as rough estimates for our isotherm analyses. Additionally, it is important to note that the model does not account for H2 physisorption, which, although weak, plays a non-negligible role in the total usable capacity of the actual material. Given calculated Langmuir isotherms, one can extract information about the usable capacity (θUC) of a particular MOF, which can be the difference in the site coverage between the loading and unloading pressures (in this work, using 100 and 5 bar as the pressure swing, we then have the definition: θUC = θ(T, 100) -θ(T, 5)). multiplied by the density of binding sites in the material and the mass of the hydrogen molecule, this dimensionless usable capacity yields the volumetric capacity, typically in g/L.