Ca K‑Edge XAS as a Probe of Calcium Centers in Complex Systems
Abstract
Herein, Ca K-edge X-ray absorption spectroscopy (XAS) is developed as a means to characterize the local environment of calcium centers. The spectra for six, seven, and eight coordinate inorganic and molecular calcium complexes were analyzed and determined to be primarily influenced by the coordination environment and site symmetry at the calcium center. The experimental results are closely correlated to time-dependent density functional theory (TD-DFT) calculations of the XAS spectra. The applicability of this methodology to complex systems was investigated using structural mimics of the oxygen-evolving complex (OEC) of PSII. It was found that Ca K-edge XAS is a sensitive probe for structural changes occurring in the cubane heterometallic cluster due to Mn oxidation. Future applications to the OEC are discussed.
Additional Information
© 2014 American Chemical Society. ACS Editors' Choice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. Received: August 15, 2014. Published: December 10, 2014. V.M.-D., D.M., V.K., and S.D. acknowledge the Max Planck Society for funding. S.D. acknowledges a Sloan Fellowship. B.G. thanks the "Université Joseph Fourier of Grenoble" for his Ph.D. grant. The Authors acknowledge support from ICMG FR 2067, COST CM1202 program (PERSPECT H2O), LABEX ARCANE (ANR-11-LABX-0003-01), the French National Research Agency (ANR-09-JCJC-0087 (MANGACOM), and ANR-13-BS07-0015-01 (MnCaOEC)) for financial support including M.G.'s and E.G.'s fellowships. We are grateful to the NIH (R01 GM102687A to T.A.); Dreyfus, Sloan, and Cottrell fellowships (T.A.); the NSF (GRFP to J.K. and E.T.); and Sandia National Laboratory (fellowship to E.T.) for funding. A portion of the XAS work was supported by NIH Grant F32GM100595 (R.T.), and by the Director of the Office of Basic Energy Science (OBES), Division of Chemical Sciences, Geosciences, and Biosciences, DOE, under contract DE-AC02-05CH11231 (J.Y). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No.DE-AC02-76SF00515. Parts of this research were carried out at the light source DORIS at DESY, a member of the Helmholtz Association (HGF). We would like to thank Dr. Edmund Welter for assistance in using beamline A.1.Attached Files
Published - ic501991e.pdf
Supplemental Material - ic501991e_si_001.pdf
Supplemental Material - ic501991e_si_002.cif
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Additional details
- PMCID
- PMC4331723
- Eprint ID
- 56032
- Resolver ID
- CaltechAUTHORS:20150324-125850453
- Max Planck Society
- Alfred P. Sloan Foundation
- Université Joseph Fourier of Grenoble
- PERSPECT H2O
- Centre National de la Recherche Scientifique (CNRS)
- ANR-11-LABX-0003-01
- Agence Nationale pour la Recherche (ANR)
- ANR-09-JCJC-0087 (MANGACOM)
- Agence Nationale pour la Recherche (ANR)
- ANR-13-BS07-0015-01 (MnCaOEC)
- Agence Nationale pour la Recherche (ANR)
- R01 GM102687A
- NIH
- Camille and Henry Dreyfus Foundation
- NSF
- Sandia National Laboratory
- F32GM100595
- NIH Postdoctoral Fellowship
- DE-AC02-05CH11231
- Department of Energy (DOE)
- DE-AC02-76SF00515
- Department of Energy (DOE)
- Cottrell Scholar of Research Corporation
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2015-03-24Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field