Inverse Design of a Catalyst for Aqueous CO/CO2 Conversion Informed by the NiII-Iminothiolate Complex

A computational inverse design method suitable to assist the development and optimization of molecular catalysts is introduced. Catalysts are obtained by continuous optimization of "alchemical" candidates in the vicinity of a reference catalyst with well-defined reaction intermediates and rate-limiting step. A Ni-II-iminoalkoxylate catalyst for aqueous CO/CO2 conversion is found with improved performance relative to a Ni-II-iminothiolate reference complex, previously reported as a biomimetic synthetic model of CO dehydroxygenase. Similar energies of other intermediates and transition states along the reaction mechanism show improved scaling relations relative to the reference catalyst. The linear combination of atomic potential tight-binding model Hamiltonian and the limited search of synthetically viable changes in the reference structure enable efficient minimization of the energy barrier for the rate-limiting step (i.e., formation of [LNiII(COOH)](-)), bypassing the exponential scaling problem of high-throughput screening techniques. The reported findings demonstrate an inverse design method that could also be implemented with multiple descriptors, including reaction barriers and thermodynamic parameters for reversible reactivity.