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Title: EXAFS analysis with self-consistent atomic potentials.

Abstract

Theoretical EXAFS spectra generated by FEFF6 and FEFF8 are compared. As a test of the effect of charge transfer on EXAFS analysis, we examine the aqueous uranyl (UO{sub 2}{sup 2+}) ion. We find that the major difference between FEFF8 and FEFF6 is the edge energy position of approximately 5 eV. Modest changes in the forward focusing multiple scattering path of the uranyl resulting with FEFF8 produce a better model of the measured hydrated uranyl spectrum.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
962873
Report Number(s):
ANL/BIO/CP-57990
TRN: US0902911
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Journal Name: AIP; Journal Volume: 882; Journal Issue: 2007; Conference: 13th International Conference on X-Rays Absorption Fine Structure (XAFS 13); Jul. 9 - Jul. 14, 2006; Stanford, CA
Country of Publication:
United States
Language:
ENGLISH
Subject:
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; ABSORPTION SPECTROSCOPY; X-RAY SPECTROSCOPY; MULTIPLE SCATTERING; URANYL COMPOUNDS

Citation Formats

Kelly, S. D., Ravel, B., and Biosciences Division. EXAFS analysis with self-consistent atomic potentials.. United States: N. p., 2007. Web.
Kelly, S. D., Ravel, B., & Biosciences Division. EXAFS analysis with self-consistent atomic potentials.. United States.
Kelly, S. D., Ravel, B., and Biosciences Division. Mon . "EXAFS analysis with self-consistent atomic potentials.". United States. doi:.
@article{osti_962873,
title = {EXAFS analysis with self-consistent atomic potentials.},
author = {Kelly, S. D. and Ravel, B. and Biosciences Division},
abstractNote = {Theoretical EXAFS spectra generated by FEFF6 and FEFF8 are compared. As a test of the effect of charge transfer on EXAFS analysis, we examine the aqueous uranyl (UO{sub 2}{sup 2+}) ion. We find that the major difference between FEFF8 and FEFF6 is the edge energy position of approximately 5 eV. Modest changes in the forward focusing multiple scattering path of the uranyl resulting with FEFF8 produce a better model of the measured hydrated uranyl spectrum.},
doi = {},
journal = {AIP},
number = 2007,
volume = 882,
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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  • Theoretical EXAFS spectra generated by FEFF6 and FEFF8 are compared. As a test of the effect of charge transfer on EXAFS analysis, we examine the aqueous uranyl (UO{sub 2}{sup 2+}) ion. We find that the major difference between FEFF8 and FEFF6 is the edge energy position of approximately 5 eV. Modest changes in the forward focusing multiple scattering path of the uranyl resulting with FEFF8 produce a better model of the measured hydrated uranyl spectrum.
  • Spectral line shapes and line strengths have long been used to diagnose plasma temperatures and densities. In dense plasmas, the additional broadening due to Stark effects give additional information about the plasma density. We present calculations that are self-consistent in that the radiation fields of the line transitions and the atomic kinetics are iterated to convergence. Examples are given for simple plasmas with temperature gradients, density gradients, and velocity fields. Then a more complex example of a laser produced plasma is presented.
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