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
Comparison between XAS and EELS
| In both electron energy loss spectroscopy (EELS) and X-ray absorption spectroscopy (XAS) measurements, the edge excitation spectrum of chemical elements can be recorded in the similar way. Table 4777 lists the comparison between XAS and EELS measurements.
Table 4777. Comparison between XAS and EELS measurements.
| |
XAS (X-ray Absorption Spectroscopy) |
EELS (Electron Energy Loss Spectroscopy) |
| Lateral resolution |
30 nm if it is performed
using synchrotron radiation focused by a zone plate |
< 1 nm |
| Interaction with matter |
Weaker interaction of photons with matter |
|
| Specimen |
Thicker specimen (easier specimen preparation) |
Thinner specimen |
| Environment |
Can examine a
specimen surrounded by air or water vapour |
Only can examine a specimen in a high vacuum |
| Equivalent term 1 |
X-ray absorption near-edge structure (XANES): worse spatial resolution |
Energy loss near edge structure (ELNES): Greater spatial resolution |
| Equivalent term 2 |
Extended X-ray absorption fine structure (EXAFS): worse spatial resolution |
Extended energy loss fine structure (EXELFS): Greater spatial resolution |
| Important difference |
X-rays transfer all their energy by ejecting electrons from their initial state in the material |
Incoming electrons lose only a fraction of their energy in the excitation process |
|
|
|
White lines are the outstanding features observed in the electron-energy-loss spectra (EELS) and x-ray-absorption spectra (XAS) of transition metals, presented at the onsets of the L2 and L3 absorption edges.
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