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Title: Improving Resolution in k and r Space: A FEFF-based Wavelet for EXAFS Data Analysis

Abstract

Applying a wavelet analysis based on the Morlet mother function, we previously demonstrated the presence of both Al and Zn atoms in the first metal shell (r {approx_equal} 3 A from the central Zn atom) of Zn-Al layered double hydroxide (LDH). However, this approach was not suited to resolve the second and third metal shells (r {approx_equal} 5 - 6 A) in r and k space independently. Therefore, we developed a new FEFF-Morlet wavelet, where the EXAFS function itself, extracted from the FEFF model, is combined with the complex Morlet wavelet. With this method, we were able to distinguish the second metal shell (Zn atoms only) from the third metal shell (Zn and Al atoms), thereby proving a regular, dioctahedral distribution of Zn atoms in the hydroxide layers.

Authors:
;  [1];  [2];  [3];  [4]
  1. Research Centre Rossendorf, Institute of Radiochemistry, Dresden (Germany)
  2. (BM20), Grenoble (France)
  3. Institute of Microelectronics Technology RAS, Chernogolovka (Russian Federation)
  4. Institute of Terrestrial Ecology, Swiss Federal Institute of Technology (ETH) Zurich (Switzerland)
Publication Date:
OSTI Identifier:
21054730
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644433; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; ALUMINIUM; ALUMINIUM COMPOUNDS; COMPUTER CALCULATIONS; DATA ANALYSIS; DISTRIBUTION; F CODES; FINE STRUCTURE; HYDROXIDES; LAYERS; RESOLUTION; X-RAY SPECTRA; X-RAY SPECTROSCOPY; ZINC; ZINC COMPOUNDS

Citation Formats

Funke, H., Scheinost, A. C., Rossendorf Beamline at ESRF, Chukalina, M., and Voegelin, A. Improving Resolution in k and r Space: A FEFF-based Wavelet for EXAFS Data Analysis. United States: N. p., 2007. Web. doi:10.1063/1.2644433.
Funke, H., Scheinost, A. C., Rossendorf Beamline at ESRF, Chukalina, M., & Voegelin, A. Improving Resolution in k and r Space: A FEFF-based Wavelet for EXAFS Data Analysis. United States. doi:10.1063/1.2644433.
Funke, H., Scheinost, A. C., Rossendorf Beamline at ESRF, Chukalina, M., and Voegelin, A. Fri . "Improving Resolution in k and r Space: A FEFF-based Wavelet for EXAFS Data Analysis". United States. doi:10.1063/1.2644433.
@article{osti_21054730,
title = {Improving Resolution in k and r Space: A FEFF-based Wavelet for EXAFS Data Analysis},
author = {Funke, H. and Scheinost, A. C. and Rossendorf Beamline at ESRF and Chukalina, M. and Voegelin, A.},
abstractNote = {Applying a wavelet analysis based on the Morlet mother function, we previously demonstrated the presence of both Al and Zn atoms in the first metal shell (r {approx_equal} 3 A from the central Zn atom) of Zn-Al layered double hydroxide (LDH). However, this approach was not suited to resolve the second and third metal shells (r {approx_equal} 5 - 6 A) in r and k space independently. Therefore, we developed a new FEFF-Morlet wavelet, where the EXAFS function itself, extracted from the FEFF model, is combined with the complex Morlet wavelet. With this method, we were able to distinguish the second metal shell (Zn atoms only) from the third metal shell (Zn and Al atoms), thereby proving a regular, dioctahedral distribution of Zn atoms in the hydroxide layers.},
doi = {10.1063/1.2644433},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
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