We have extended the Universal Force Field for to cover all moieties present in the most extensive framework library to date, i.e. the Computation-Ready Experimental (CoRE) database (Chem. Mater. 26, 6185 (2014)).Thus, we have extended the parameters to include the fourth and fifth row transition metals, lanthanides and an additional atom type for Sulphur, while the parameters of original UFF and of UFF4MOF are not modified. Employing the new parameters significantly enlarges the number of structures that may be subjected to a UFF calculation, i.e. more than doubling accessible MOFs of the CoRE structures and thus reaching over 99% of CoRE structure coverage. In turn, 95% of optimized cell parameters are within 10% of their experimental values. We contend these parameters will be most useful for the generation and rapid prototyping of hypothetical MOF structures from SBU databases.

We report herein a comprehensive theoretical study of the thermodynamics and kinetics of molecular hydrogen activation by frustrated Lewis pairs (FLPs). A series of intermolecularly combined boranes (Lewis acids) and phosphines (Lewis bases), with experimentally established different reactivities towards H2, have been subjected to DFT and (SCS‐)MP2 calculations, and analyzed in terms of their structural properties, the energetics of association of the FLPs, and the kinetics of their interactions with H2 and hydrogenation to the ion‐pair products. The analysis included the following steps: 1) assessment of the ability/inability of the Lewis species to preorganize into FLPs with an optimum arrangement of the acid and base sites for preconditioning the reaction with H2, 2) comprehension of the different thermodynamics of hydrogenation of the selected FLPs by comparing the Gibbs energies of the overall reactions, and 3) estimation of the mechanism of the activation of H2 by identifying the reaction steps and the associated kinetic barriers. The results of our studies correlate well with experimental findings and have clarified the reasons for the observed different reactivities of the investigated systems, ranging from reversible or nonreversible activation to no reaction with H2. The derived predictions could assist the future design of Lewis acid–base systems with desired properties and applicability as metal‐free hydrogenation catalysts.

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