Measuring the energy of the graphite π + σ plasmon peak

We examine the graphite plasmon loss structure in reflection electron energy loss spectroscopy (REELS) and XPS with respect to the issue of measuring the energy, Ep, of the π + σ plasmon peak. The two spectra differ in shape because they are based on different physical processes. In fact, a static core hole—leading to intrinsic (in addition to extrinsic) losses—exists only for XPS. We show that no single energy can be measured on the two spectra for the π + σ peak. Possible procedures to deal with the matter are considered. Copyright © 2006 John Wiley & Sons, Ltd.