Direct Detection of Oxygen Ligation to the Mn4Ca Cluster of Photosystem II by X-ray Emission Spectroscopy

Authors


  • This work was supported by the NIH grant (GM 55302) and the DOE, Director, Office of Science, Office of Basic Energy Sciences (OBES), Chemical Sciences, Geosciences, and Biosciences Division, under Contract DE-AC02-05CH11231. Portions of this research were carried out at SSRL, operated by Stanford University for DOE, OBES. The SSRL SMB Program is supported by the DOE, OBER and by the NIH, NCRR. We thank Prof. Steve Cramer for the use of his emission spectrometer (NIH Grant EB-001962) for some of the work and Prof. Ken Sauer for many useful discussions.

Abstract

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O im Blick: Mn-Kβ2,5- und -Kβ′′-Emissionsspektren entstehen durch Übergänge von den Ligand-2s- und -2p-Schalen der Metallkomplexe in die 1s-Metallniveaus. Auf diese Weise konnten die O-Liganden des Mn4Ca-Clusters untersucht werden, der die photosynthetische Wasserspaltung katalysiert, was erstmals den direkten Nachweis der verbrückenden Oxogruppen an Mn ermöglichte.

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