Probing the [FeFe]-hydrogenase subsite using muon spectroscopy

Understanding the fundamental steps by which reactions take place is vitally important for developing new chemical systems. In this research, we will use unstable particles called muons to probe a catalyst which releases hydrogen. Muons react with our metal-containing chemicals in much the same way as hydrogen, but because of their characteristics of radioactive decay, it is possible to monitor the evolution of their spin when implanted within a sample, and thus gain information such as the addition site and reaction mechanisms. In these experiments, we will add muons to two of our catalysts in solution, which will enable us to gain new insight into how these molecules behave.

Fundamental understanding of the routes by which metal complexes react with protons/electrons is essential for the development of new molecular catalysts for the production of dihydrogen. While this proposal only addresses one system, and thus a small part of the question, the combination of this and other work will contribute to our understanding of the development of new catalytic systems. Efficient production of dihydrogen as an energy vector has the potential for major impact on society energy use, and thus the construction of an accurate picture of the routes by which protons are activated at metal centres is an important research target. More widely, by exploiting muon spectroscopy in the development of our understanding of protonation of di-iron systems, we will demonstrate the power the the technique in probing protonation reactions at metal centres. Take up by other workers focussing on various metal-mediated protonations may well follow from this work.