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arXiv · 2010.10364

Low-Energy Electron Diffraction With Energy Invariant Carrier Wave Wavenumber Modulated by Exchange-Correlation Interaction

John Rundgren·Bo E. Sernelius·Wolfgang Moritz
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Abstract

We present low-energy electron diffraction (LEED) as elastic electron-atom scattering (EEAS) operating in a target crystal waveguide where a Coulombic carrier wave is wavenumber modulated by exchange-correlation (XC) interaction. Carrier potential is designed using a KKR (Korringa-Kohn-Rostoker) muffin-tin model built on overlapping free atoms. XC potential is constructed using Sernelius's many-particle theory on electron self-energy. EEAS phase shifts are derived from Dirac's differential equations, and four recent LEED investigations are recalculated: Cu(111)+$( 3\!\surd3\times\!\surd3 ) \mathrm{R30^\circ}$-TMB, Ag(111)+$(4\!\times \!4 )$-O, Ag(111)+$( 7\!\times\!\surd3 ) \mathrm{rect}$-$\mathrm{SO}_4$, Ru(0001)+$( \surd3\!\times\!\surd3 ) \mathrm{R30^\circ}$-C. TMB stands for 1,3,5-tris(4-mercaptophenyl)-benzene with chemical formula C$_{24}$H$_{15}$S$_3$. We are able to report substantially improved reliability factors.

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John Rundgren, Bo E. Sernelius, Wolfgang Moritz. 2020-10-20. Low-Energy Electron Diffraction With Energy Invariant Carrier Wave Wavenumber Modulated by Exchange-Correlation Interaction. https://arxiv.org/abs/2010.10364

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