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Lecture 14
X-ray absorption, fluorescence,
and diffraction
Na 1s22s22p63s1
Outer electrons
-5 eV
3s
A
X-ray absorption
-63eV
2s2p
E,eV
0
1
E,keV
el=1.17 nm
-1072 eV
1s
1s22s22p63s1
Inner electrons
Na atom
-5 eV
3s
I
X-ray fluorescence
-63eV
2s2p
E,eV
0
ehn
-1072 eV
1s
1
E,keV
Almost no chemical shift
1s22s22p63s1
Na atom
K-line
Moseley Law
E
L-line
K
L
Atomic number
AP + PC = dsin + dsin
nl = 2dsin
A bank note XRF “fingerprint”
Energy dispersive
XRF spectrometer
Si(Li) detector
Each X-ray photon is converted into an electric charge proportional to its
energy (1 e- for 4 eV) and the signal is analyzed by a multichannel detector
X-ray diffraction
Debye-Scherrer powder camera
Auger electron spectroscopy
Li to F