Spectroscopic Signatures of the Fe₂O₂ Diamond Core

Due to the availability of synthetic precedents, the Fe₂(μ-O)₂ diamond core has emerged as an attractive candidate for the core structures of the high-valent intermediates of nonheme diiron enzymes such as methane monooxygenase and ribonucleotide reductase. Such cores have spectroscopic signatures that distinguish them from other proposed structures, particularly the Fe=O moiety associated with high-valent states of heme enzymes. The Mössbauer, Raman, and EXAFS features of the Fe₂(μ-O)₂ diamond core can be used to ascertain whether the high-valent intermediates of methane monooxygenase and ribonucleotide reductase utilize such structures to access the iron(IV) oxidation state.