![A spectroscopic mimic of the oxygen evolving complex](/sites/g/files/dgvnsk196/files/styles/sf_landscape_16x9/public/images/article/Picture1_5.png?h=3873714b&itok=B07hxfWp)
A spectroscopic mimic of the oxygen evolving complex
The oxygen evolving complex (OEC) of photosystem II catalyzes the oxidation of water to form molecular oxygen. The S₃-state is currently the last observable intermediate prior to O–O bond formation. Its electronic structure has been assigned to a homovalent Mn(IV)₄ core with an S = 3 ground state. In a recent publication (Lee, Marchiori, et al. JACS), the Agapie (Caltech) and Britt labs synthesized and characterized via XAS and multifrequency EPR spectroscopy a Mn(IV)₄O₄ cuboidal complex. Results show that this Mn(IV)₄O₄ complex has an S = 3 ground state and magnetic parameters that mimic the OEC in the S₃-state. This spectroscopic model provides a benchmark of the S₃-state and furthers our understanding of the OEC just prior to O–O bond formation.
More information at https://doi.org/10.1021/jacs.9b10371