Photochemistry of iron carbene complexes

This project will investigate the excited state reactivity of a recently discovered class of iron complexes featuring unique nanosecond lifetimes and sizable luminescence quantum yields of their charge-transfer excited states that approach the favorable properties of the archetypal ruthenium oligopyridyl photosensitizers.

The reactivity of the excited 3MLCT and 2LMCT states towards molecular donors and acceptors will be studied by luminescence quenching and transient absorption techniques to infer rate constants and yields of electron transfer and excitation energy transfer reactions.

Due to the inversed charge distribution and exceptional spin multiplicity, the reactivity of the highly unusual 2LMCT states of the Fe(III) complexes can be anticipated to deviate fundamentally from the behavior of the common 3MLCT states of established transition metal photosensitizers and of the excited singlet and triplet states of organic dyes.

We also intend to demonstrate the utility of the iron complexes for the light induced formation of reactive intermediates in organic synthesis and to investigate the generation of the luminescent states in electrochemically triggered electron transfer reactions.

From the outcome of this study it will be possible to evaluate the potential of these iron complexes to replace precious metal photosensitizers and luminophores for e.g. solar energy conversion, photoredox catalysis or electro(chemi)luminescence applications.