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Monte Carlo Simulations of Electron Energy-Loss Spectra with the Addition of Fine Structure from Density Functional Theory Calculations

Published online by Cambridge University Press:  25 February 2016

Mohammad Attarian Shandiz*
Affiliation:
Department of Materials Engineering, McGill University, Montreal, H3A 0C5, Canada
Maxime J.-F. Guinel
Affiliation:
Departments of Chemistry and Physics, College of Natural Sciences, University of Puerto Rico, San Juan, PR 00936, USA
Majid Ahmadi
Affiliation:
Department of Physics, College of Natural Sciences, University of Puerto Rico, San Juan, PR 00936, USA
Raynald Gauvin
Affiliation:
Department of Materials Engineering, McGill University, Montreal, H3A 0C5, Canada
*
*Corresponding author. [email protected]
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Abstract

A new approach is presented to introduce the fine structure of core-loss excitations into the electron energy-loss spectra of ionization edges by Monte Carlo simulations based on an optical oscillator model. The optical oscillator strength is refined using the calculated electron energy-loss near-edge structure by density functional theory calculations. This approach can predict the effects of multiple scattering and thickness on the fine structure of ionization edges. In addition, effects of the fitting range for background removal and the integration range under the ionization edge on signal-to-noise ratio are investigated.

Type
Techniques, Software, and Equipment
Copyright
© Microscopy Society of America 2016 

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