Abstract
In exchange-coupled mixed-valence spin systems, the magnitude and sign of the effective ligand hyperfine interaction (HFI) can be useful in determining the formal oxidation state of the coordinating metal ion, as well as provide information about the coordination geometry. This is due to the fact that the observed ligand HFI is a function of the projection factor (Clebsch-Gordon coefficient) that maps the site spin value S i of the local paramagnetic center onto the total spin of the exchange-coupled system, S T. Recently, this relationship has been successfully exploited in identifying the oxidation state of the Mn ion coordinated by the sole nitrogenous ligand to the oxygen-evolving complex in certain states of photosystem II. The origin and evolution of these efforts is described.
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The authors acknowledge the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences of the U.S. Department of Energy through Grant DE-FG02-11ER16282 for funding the PSII research conducted in the Britt Laboratory.
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Paul H. Oyala and Troy A. Stich authors contributed equally to this work.
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Oyala, P.H., Stich, T.A. & Britt, R.D. Metal ion oxidation state assignment based on coordinating ligand hyperfine interaction. Photosynth Res 124, 7–18 (2015). https://doi.org/10.1007/s11120-015-0086-0
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DOI: https://doi.org/10.1007/s11120-015-0086-0