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Title: The difficult chore of measuring coordination by EXAFS.

Abstract

Neither the theory nor the interpretation of Extended X-Ray-Absorption Fine-Structure (EXAFS) spectroscopy requires assumptions of crystalline symmetry or periodicity. As a result, EXAFS is a tool applied to a wide range of scientific disciplines and to a wide variety of experimental systems. A simple enumeration of the atoms in the coordination environment of the absorber is often the primary goal of an EXAFS experiment. There are, however, a number of pitfalls in the way of an accurate determination of coordination number (CN). These include statistical limitations of the EXAFS fitting problem, empirical effects due to sample preparation, and the assumptions made about the physical structure surrounding the absorber in the course of data analysis. In this paper we examine several of these pitfalls and their effects upon the determination of CN. Where possible, we offer suggestions for avoiding or mitigating the pitfalls. We hope this paper will help guide the general EXAFS practitioner through the difficult chore of accurately determining CN.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
973753
Report Number(s):
ANL/BIO/CP-119074
TRN: US201006%%965
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: 13th International Conference on X-ray Absorption Fine Structure (XAFS13); Jul. 9, 2006 - Jul. 14, 2006; Stanford, CA
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION SPECTROSCOPY; X-RAY SPECTROSCOPY; COORDINATION NUMBER; DATA ANALYSIS; FINE STRUCTURE; SAMPLE PREPARATION; RECOMMENDATIONS

Citation Formats

Ravel, B., Kelly, S. D., and Biosciences Division. The difficult chore of measuring coordination by EXAFS.. United States: N. p., 2007. Web. doi:10.1063/1.2644458.
Ravel, B., Kelly, S. D., & Biosciences Division. The difficult chore of measuring coordination by EXAFS.. United States. doi:10.1063/1.2644458.
Ravel, B., Kelly, S. D., and Biosciences Division. Mon . "The difficult chore of measuring coordination by EXAFS.". United States. doi:10.1063/1.2644458.
@article{osti_973753,
title = {The difficult chore of measuring coordination by EXAFS.},
author = {Ravel, B. and Kelly, S. D. and Biosciences Division},
abstractNote = {Neither the theory nor the interpretation of Extended X-Ray-Absorption Fine-Structure (EXAFS) spectroscopy requires assumptions of crystalline symmetry or periodicity. As a result, EXAFS is a tool applied to a wide range of scientific disciplines and to a wide variety of experimental systems. A simple enumeration of the atoms in the coordination environment of the absorber is often the primary goal of an EXAFS experiment. There are, however, a number of pitfalls in the way of an accurate determination of coordination number (CN). These include statistical limitations of the EXAFS fitting problem, empirical effects due to sample preparation, and the assumptions made about the physical structure surrounding the absorber in the course of data analysis. In this paper we examine several of these pitfalls and their effects upon the determination of CN. Where possible, we offer suggestions for avoiding or mitigating the pitfalls. We hope this paper will help guide the general EXAFS practitioner through the difficult chore of accurately determining CN.},
doi = {10.1063/1.2644458},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
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  • Neither the theory nor the interpretation of Extended X-Ray-Absorption Fine-Structure (EXAFS) spectroscopy requires assumptions of crystalline symmetry or periodicity. As a result, EXAFS is a tool applied to a wide range of scientific disciplines and to a wide variety of experimental systems. A simple enumeration of the atoms in the coordination environment of the absorber is often the primary goal of an EXAFS experiment. There are, however, a number of pitfalls in the way of an accurate determination of coordination number (CN). These include statistical limitations of the EXAFS fitting problem, empirical effects due to sample preparation, and the assumptionsmore » made about the physical structure surrounding the absorber in the course of data analysis. In this paper we examine several of these pitfalls and their effects upon the determination of CN. Where possible, we offer suggestions for avoiding or mitigating the pitfalls. We hope this paper will help guide the general EXAFS practitioner through the difficult chore of accurately determining CN.« less
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