Determination of Electronic Properties Using Resonant Photoemission

2 Determination of Electronic Properties Using Resonant Photoemission 

For the determination of electronic properties photoelectron spectroscopy with variable excitation energy was carried out because it is indispensable to 

The spectra of the energy region around 20 eV binding energy for excitation energies between 100 and 140 eV are shown in Fig. 3.27a for CePd2Si2. Obviously the emission of Ce 5pia and p a is drastically increased at about 120 eV. This behavior is directly correlated with the onset of the resonant enhancement of the 4d 4/transition in the Ce compound. This process is described by 4 / 4/ + hv 4d 4/ with subsequent 4d 4/ 4d 4/ 5p + e [50]. 

Electron energy-loss spectroscopy at low excitation energies is a surface sensitive technique to study the electronic structure by exciting collective oscillations or electrons from occupied into unoccupied states. In metals with a high density of states arising from d electrons, the excitation of plasmon losses has a relatively low probability. Therefore, the spectra are dominated by interband or intraband transitions. In rare earth metals, excitations of the partially filled/shell are observed that are assigned to be dipole-forbidden 4/4/transitions. These transitions are enhanced near the 4ii-4/threshold [56]. 

The inset in Fig. 3.30 shows a t)q)ical electron energy-loss spectrum of CePd2Si2 taken at a primary energy of the incident electron beam of Fp = 27 eV. Two characteristic features are present in the spectrum a pronounced peak at 

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