Low-energy electron diffraction with signal electron carrier-wave wavenumber modulated by signal exchange-correlation interaction

Low-energy electron diffraction (LEED) is considered as elastic electron-atom scattering (EEAS) operating in a target crystal waveguide, where a signal electron carrier wave is wavenumber modulated by signal exchange-correlation (XC) interaction. A carrier potential is designed using a KKR (Korringa-Kohn-Rostoker) muffin-tin (MT) model built on overlapping MT spheres that implement atoms with double degree of freedom, radius and potential level. An 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 root 3 x root 3) R30 degrees-TMB, TMB = 1,3,5-tris(4-mercaptophenyl)-benzene with chemical formula C24H15S3; Ag(111) + (4 x 4)-O; Ag(111) + (7 x root 3)rect - SO4; and Ru(0001) + (root 3 x root 3)R30 degrees -Cl. Our EEAS phase shifts generate substantially improved reliability factors, and we report the first confirmation of electron self-energy by LEED experiment.

Automated summary

In this study, LEED was used to investigate several crystal surfaces, deriving more reliable results from EEAS phase shifts and confirming the existence of electron self-energy for the first time through LEED experimentation.