All gas-phase geometry optimizations on the MOF cluster models were performed using DFT with a development version of TeraChem v1.9. 104, 105 Cartesian constraints were applied on the first and second coordination sphere atoms from the metal to mimic the constrained ligand environment of a MOF stemming from its extended framework. The B3LYP 106-108 global hybrid functional was employed with the empirical D3 dispersion correction 109 using Becke-Johnson damping. The LACVP* composite basis set was used for all calculations, which consists of a LANL2DZ effective core potential 111, 112 for transition metals and the 6-31G* basis set 113 for all other atoms (Supporting Information Figure ). All calculations were carried out in an unrestricted formalism with level-shifting 114 of 0.25 Ha applied to both majority-and minorityspin virtual orbitals to aid self-consistent field (SCF) convergence (Supporting Information Text S5 and Figure ). Geometry optimizations were performed with the translation rotation internal coordinate (TRIC) optimizer 115 using the BFGS algorithm with default convergence thresholds of maximum energy gradient of 4.5 ´ 10 -4 hartree/bohr and energy difference between steps of 10 -6 hartree.