CHARACTERISTIC STRUCTURE IN CORE ELECTRON SPECTRA OF METALS DUE TO ELECTRON-PLASMON COUPLING

The coupling of metallic core electrons to the density fluctuations of the conduction electrons is studied. Due to the strong electron-plasmon coupling there is a characteristic satellite structure in the core electron spectrum, starting at the plasma energy h{combining short stroke overlay}ωp below the quasiparticle level and with a maximal spectral weight at (1.6-2.5)×h{combining short stroke overlay}ωp below the same level. The total spectral weight in the satellite band is 50-100 percent of the quasiparticle weight, the actual value dependent on the density of the conduction electrons. The possible implications on X-ray photoemission, soft X-ray emission and absorption, and inelastic scattering of electrons are drawn. Particularly, a close correspondence with the location of the fine structure of the L2,3 absorption spectrum of Al is found. The relation to the cohesive energy is also considered. © 1969 Springer-Verlag.