Fe2S2 centers models

The Fe2S2 center shows nicely how spectroscopy can be used to deduce the structure of an active site. Indeed, in this case the now well-established active-site structure was deduced by a combination of chemical, spectroscopic, and magnetic methods, and the site was successfully modeled long before the first protein crystallographic study was reported. 

Efforts toward developing synthetic models for the Rieske Fe-S centers focussed initially on preparing Fe2S2 cores with non-thlolate ligands, and have centered on nitrogenous ligands since the realization of their probable occurrence in the Rieske protein. In addition to the [Fe2S2(0Ar) ] " ions (Ar = aryl)... 

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