Orientation Selected Endor Studies of a Manganese Dimer

  • M. Baumgarten
  • J. S. Sheats
  • G. C. Dismukes
Conference paper


Bi- and polynuclear Mn-containing active sites of biological material are responsible for the reduction of ribonucleotides in bacteria, disproportio- nation of hydrogeneperoxide by cataiases and most important for the photosynthetic oxidation of water to oxygen in higher plants and cyano- bacteria. For the photosynthetic watersplitting four Mn-ions are necessary and during light driven turnovers of the Photosystem II (PSII) they adopt different, partially stable oxidation states (S0-S4) involving metal oxidation states in the range II-IV. In recent efforts to model the complex Mn-cluster synthetically prepared Mn-dimers were often used1. Their EPR characteristic is a well known 16 line hf pattern in the MnIII MnIV oxidation state comparable to the “multiline” signal around g=2 of the S2 state of PSII.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • M. Baumgarten
    • 1
  • J. S. Sheats
    • 2
  • G. C. Dismukes
    • 3
  1. 1.Max Planck Institut für PolymerforschungMainzGermany
  2. 2.Rider CollegeLawrencevilleUSA
  3. 3.Dept. of ChemistryPrinceton UniversityPrincetonUSA

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