1. Soft x-ray absorption spectroscopy of metalloproteins and high-valent metal-complexes at room temperature using free-electron lasers
- Author
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Kubin, Markus, Kern, Jan, Gul, Sheraz, Kroll, Thomas, Chatterjee, Ruchira, Löchel, Heike, Fuller, Franklin D, Sierra, Raymond G, Quevedo, Wilson, Weniger, Christian, Rehanek, Jens, Firsov, Anatoly, Laksmono, Hartawan, Weninger, Clemens, Alonso-Mori, Roberto, Nordlund, Dennis L, Lassalle-Kaiser, Benedikt, Glownia, James M, Krzywinski, Jacek, Moeller, Stefan, Turner, Joshua J, Minitti, Michael P, Dakovski, Georgi L, Koroidov, Sergey, Kawde, Anurag, Kanady, Jacob S, Tsui, Emily Y, Suseno, Sandy, Han, Zhiji, Hill, Ethan, Taguchi, Taketo, Borovik, Andrew S, Agapie, Theodor, Messinger, Johannes, Erko, Alexei, Föhlisch, Alexander, Bergmann, Uwe, Mitzner, Rolf, Yachandra, Vittal K, Yano, Junko, and Wernet, Philippe
- Subjects
Inorganic Chemistry ,Chemical Sciences ,Physical Sciences ,Physical chemistry ,Condensed matter physics ,Particle and high energy physics - Abstract
X-ray absorption spectroscopy at the L-edge of 3d transition metals provides unique information on the local metal charge and spin states by directly probing 3d-derived molecular orbitals through 2p-3d transitions. However, this soft x-ray technique has been rarely used at synchrotron facilities for mechanistic studies of metalloenzymes due to the difficulties of x-ray-induced sample damage and strong background signals from light elements that can dominate the low metal signal. Here, we combine femtosecond soft x-ray pulses from a free-electron laser with a novel x-ray fluorescence-yield spectrometer to overcome these difficulties. We present L-edge absorption spectra of inorganic high-valent Mn complexes (Mn ∼ 6-15 mmol/l) with no visible effects of radiation damage. We also present the first L-edge absorption spectra of the oxygen evolving complex (Mn4CaO5) in Photosystem II (Mn
- Published
- 2017