EELS of Collective Surface Modes
Vibrational modes of the Cu(100) — CO system have been investigated by inelastic electron scattering. The C-O stretching vibrational mode of the Cu(100) c(2×2)CO system is found to be collective. The mode dispersion is dominated by dipole-dipole interaction. A low-energy mode which is observed to be particularly pronounced for the c(2×2)CO structured situation is interpreted to be due to the excitation of a surface phonon at the M point of the substrate surface Brillouin zone.
KeywordsElectron Energy Loss Spectroscopy Loss Peak Dipole Excitation Surface Phonon Mode Dispersion Relation
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