Electron microscopy
 
Crystal Orientation/Diffraction Effects on EXELFS of EELS Signals
- Practical Electron Microscopy and Database -
- An Online Book -
Microanalysis | EM Book                                                                                   http://www.globalsino.com/EM/        

=================================================================================

 

In the energy region of more than 50 eV after the core edge in EELS, EXELFS with small intensity oscillations, due to diffraction effects from the atoms, may be detectable. For instance, for carbon nanotubes and graphite, as shown in Figure 3171, not only does the core electron EELS spectra for the nanotubes shift to lower energies from those of graphite due to their lower-dimensional feature and thus due to the lower carrier densities and conductivities than graphite, but also the EELS on both the tubule bundle and graphite are sensitive to the incident electron beam along their crystalline axis.

Core electron EELS spectra for both nanotubes and graphite with incident electron along their different crystal orientations

Figure 3171. Core electron EELS spectra for both nanotubes and graphite with the incident electron in TEM along their different crystal orientations. Adapted from [1]

 

 

 

 

 

 

 

 

[1] V.P. Dravid, X. Lin, Y. Wang, X. K. Wang, A. Yee, J. B. Ketterson, and R. P. H. Chang. Science, 259, 1601 (1993).

 

=================================================================================