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Title: Temperature and radiation effects at the fluorine K-edge in LiF

Abstract

Here, the fluorine K-edge of LiF is studied both experimentally and theoretically as a function of temperature. Instantaneous thermal fluctuations in atomic positions are shown in molecular dynamics simulations to increase in amplitude from 0.029 to 0.064 nm in the temperature range from 40 to 298 K. This is sufficient to cause instantaneous deviations from local octahedral atomic symmetry in this rock-salt crystal, resulting in altered electronic structure. The lowered symmetry of the lowest core-excited states of fluorine atoms is evident in X-ray absorption spectra at the F K-edge. In addition, sufficient radiation exposure produces a new X-ray absorption peak, below the F K-edge of LiF, which is assigned to defects in LiF based on both calculations and comparison to previous experiments.

Authors:
 [1];  [2];  [3];  [4];  [5];  [6]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, Davis, CA (United States)
  3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  4. Univ. of California, Davis, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  5. National Inst. of Standards and Technology (NIST), Boulder, CO (United States)
  6. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1374536
Alternate Identifier(s):
OSTI ID: 1413832
Grant/Contract Number:
AC02-76SF00515; AC02-05CH11231; AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Electron Spectroscopy and Related Phenomena
Additional Journal Information:
Journal Volume: 218; Journal Issue: C; Journal ID: ISSN 0368-2048
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; NEXAFS; XANES; Rock-salt; Temperature effects

Citation Formats

Schwartz, Craig P., Ponce, Francisco, Friedrich, Stephan, Cramer, Stephen P., Vinson, John, and Prendergast, David. Temperature and radiation effects at the fluorine K-edge in LiF. United States: N. p., 2017. Web. doi:10.1016/j.elspec.2017.05.007.
Schwartz, Craig P., Ponce, Francisco, Friedrich, Stephan, Cramer, Stephen P., Vinson, John, & Prendergast, David. Temperature and radiation effects at the fluorine K-edge in LiF. United States. doi:10.1016/j.elspec.2017.05.007.
Schwartz, Craig P., Ponce, Francisco, Friedrich, Stephan, Cramer, Stephen P., Vinson, John, and Prendergast, David. Tue . "Temperature and radiation effects at the fluorine K-edge in LiF". United States. doi:10.1016/j.elspec.2017.05.007.
@article{osti_1374536,
title = {Temperature and radiation effects at the fluorine K-edge in LiF},
author = {Schwartz, Craig P. and Ponce, Francisco and Friedrich, Stephan and Cramer, Stephen P. and Vinson, John and Prendergast, David},
abstractNote = {Here, the fluorine K-edge of LiF is studied both experimentally and theoretically as a function of temperature. Instantaneous thermal fluctuations in atomic positions are shown in molecular dynamics simulations to increase in amplitude from 0.029 to 0.064 nm in the temperature range from 40 to 298 K. This is sufficient to cause instantaneous deviations from local octahedral atomic symmetry in this rock-salt crystal, resulting in altered electronic structure. The lowered symmetry of the lowest core-excited states of fluorine atoms is evident in X-ray absorption spectra at the F K-edge. In addition, sufficient radiation exposure produces a new X-ray absorption peak, below the F K-edge of LiF, which is assigned to defects in LiF based on both calculations and comparison to previous experiments.},
doi = {10.1016/j.elspec.2017.05.007},
journal = {Journal of Electron Spectroscopy and Related Phenomena},
number = C,
volume = 218,
place = {United States},
year = {Tue May 30 00:00:00 EDT 2017},
month = {Tue May 30 00:00:00 EDT 2017}
}

Journal Article:
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  • The solid electrolyte interface (SEI) formation on the surface of LiMn{sub 2}O{sub 4} electrodes during room temperature charge-discharge cycling was studied using soft X-ray absorption spectroscopy at the Fluorine (F) K-edge. LiMn{sub 2}O{sub 4} electrodes without any binder were prepared by electrostatic spray deposition to eliminate the signal originating from the PVDF binder in the F K-edge X-ray absorption spectra. The F K-edge absorption spectra show that the SEI layer forms at a very early stage of cycling. SEI growth takes place during discharge. In addition, LiF formation is accelerated if the discharge step follows a charge step. The Fmore » K-edge absorption spectra suggest that the major component of the SEI is LiF.« less
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