Electron Distribution and Coupling

The Mossbauer spectral data in Table V, drawn from a larger data set for clusters with varying coordination number at the unique subsite (219), illustrate how the isomer shift and quadrupole splitting of that subsite can 

In addition to producing biased electron distributions in the otherwise symmetrically delocalized [4Fe-4Sp core, subsite-specific substitution can 

The structure at the unique subsite of 55 may resemble that of the Fe(CO)3 subsites in Fe4S4(CO)i2 (232), in which case longer Fe-Fe and Fe-S distances will tend to separate this subsite from the others. Normally, the [4Fe-4S] core of protein and analogue clusters are characterized by close or exact tetragonal symmetry. 

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