So far in this volume, we have neglected a seemingly obvious effect in PES, namely the scattering of the photoexcited electron on its way through the crystal to the surface, by the crystal potential. This is a straightforward scattering problem leading to intensity modulations as a function of electron wavelength and/or crystal orientation. Such intensity modulations have indeed been observed and the method of measuring PES in order to bring out most clearly the scattering features of the final-state electron intensity is called PhotoElectron Diffraction (PED).
KeywordsPolar Angle Forward Scattering EXAFS Data Bulk Plasmon Photoelectron Diffraction
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