Building the ideal rest stop for protons
Where protons, or positive charges, decide to rest makes the difference between proceeding towards ammonia (NH3) production or not, according to scientists at Pacific Northwest National Laboratory (PNNL) and Villanova University. By designing and examining the reactivity of five complexes with molybdenum metal centers, the team found that subtle differences in the complexes greatly change where the protons end up. The differences were in the structure of the ligands, molecular frameworks that surround the metal. When the ligands were more willing than a metal-bound dinitrogen group to take in a proton, the protons ended up binding with the molybdenum center, essentially ending up stuck in the wrong place. But when the ligands ability to accept protons was more closely matched with that of the dinitrogen group, the protons ended up going to the desired location for producing NH3.
