Atomic inner shell excitations with eels in REM: Pt and Au M4,5 edge shapes modifications in REM

Abstract

Electron energy-loss spectroscopy (EELS) has been used in parallel with reflection electron microscopy (REM) to investigate the inner shell structure of the surface atoms in bulk single crystals of Pt and Au. A Phillips 400T TEM is used for the experiment, with the arrangement shown in fig. 4. The observed M4,5 edge from the bulk crystal surface (REM case) is compared with that from a thin metal foil (TEM case), such that the surface atomic inner shell modifications, relative to the atoms in the bulk, can be obtained. Fig. 1(A) and 1(B) show the REM image of the Pt (111) surface and the corresponding EELS Pt-M4,5 edge. This observed edge in the REM case is compared with the edge observed in the TEM from a thin Pt foil (fig.l(B)). Comparing the results in fig 1(B) and fig. 2(B) for the REM and TEM cases, the shape modification at the M4,5 edge maximum part is related to the strong multiple surface plasmon scattering[l].