Theory of Intrinsic and Extrinsic Plasmon Excitation in Deep Core XPS Spectra

Intrinsic and extrinsic plasmon loss effects are discussed based on the theory proposed by the present author, both for surface and bulk plasmon loss observed in XPS spectra from deep cores. Two types of the incident X-ray polarization are considered here; one is normal to the surface, another is parallel to it. The angular distribution is also discussed for electrons emitted from the cores at various depth. Model calculations are carried out for the photoemission from Al K-shell, which show the importance of interference between intrinsic and extrinsic effects for any polarization, and any direction especially for the excitation by low energy photons. In this case loss spectra are featureless and would lost in the background.