Nitrogen fixation, a critical process for sustaining life on Earth, plays an essential role in the global nitrogen cycle, and provides bioavailable nitrogen for the growth and development of all living organisms. Although the atmosphere is composed of approximately 78% nitrogen, its inert nature renders it inaccessible to most life forms. Nature has evolved an intricate mechanism to overcome this barrier, primarily through the activity of nitrogenfixing microorganisms capable of reducing dinitrogen (N 2 ) into bioavailable forms such as ammonia (NH 3 ). Nitrogen fixation driven by transition metal complexes offers a less energy intensive alternative to the conventional Haber-Bosch process . These complexes can effectively catalyze the conversion of N 2 to NH 3 under similar conditions as the nitrogenase enzymes in nature. A key breakthrough was Schrock's discovery of molybdenum-based complexes capable of binding and reducing dinitrogen to ammonia under ambient conditions. His work led to the development of the first well-defined, homogeneous catalyst containing a single metal site for nitrogen fixation, known as the Schrock catalyst ([Mo( HIPT N 3 N)]) . This molybdenum-based catalyst operates through a series of proton-coupled electron transfer steps, which reduce dinitrogen to ammonia. The Schrock catalyst represents a significant milestone in the field of small molecule nitrogen fixation, as it was the first well-defined, homogeneous catalyst containing a single metal site capable of converting dinitrogen to ammonia. However, its practical application in large-scale nitrogen fixation has been limited due to several factors, including low turnover numbers . The Schrock catalyst is the best studied molecular catalyst for dinitrogen reduction, both computationally and experimentally and studies indicate that the last steps in the catalytic cycle are the energetic bottlenecks. For example, the equilibrium constant for replacing NH 3 with N 2 on the catalyst (NH 3 --⇀ ↽--N 2 ) has been experimentally measured to be about 0.1, and the reaction energy of the final reduction step (NH 3 + --→ NH 3 ) has been measured to be between 0 and 1 kcal/mol . These findings have been further corroborated and augmented by DFT calculations by Reiher, Neese, Tuczek and others . For example, Figure shows the catalytic cycle and the corresponding DFT-free energy profile computed by Thimm et al . While this energy profile shows a large energy increase upon the addition of the first proton (N 2 --→ NNH + ) computational studies by Schenk et al. found a more facile route where the proton first binds to one of the N atoms on the ligand before transferring to the bound dinitrogen. Therefore, both DFT free energy calculations and experiments suggest that the main bottlenecks are the last reduction step NH 3 + --→ NH 3 and/or the displacement reaction of a bound NH3 for N2 (NH 3 --→ N 2 ). Further computation studies by Schenk et al. indicate two possible paths for the displacement step. Release of NH 3 followed by uptake of N 2 , or via an intermediate state where both NH 3 and N 2 are bound to the molybdenum atom (NH 3 -N 2 ).