Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix
| The interpretation of the features of low-loss regions in EELS from free-electron metals is fairly straightforward because the signals arise mainly from bulk and surface plasmon excitations and the energies of the peaks from bulk (Ebulk) and surface (Esurface) plasmon excitations have the simple relationship given by, Ebulk = √2Esurface -------------------------- [2306] On the other hand, the interpretation of the features of the low-loss regions from transition metals is more difficult because of some factors. In transition metals, both plasmon losses and interband transitions induce energy loss and the plamon losses generally do not occur at the energies theoretically predicted by free-electron model. Different from the case presented in Equation 2306 for free-electron metals, there is no simple relationship between the bulk and surface plasmon loss energies for a transition metal due to too much dependence on the band structure. Moreover, some electrons in certain d-bands may not be able to participate in collective plamon oscillations.
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