Ego says, "Once everything falls into place, I'll feel peace." Spirit says "Find your peace, and then
Idea Transcript
Diffraction methods for structures analysis Diffraction of waves from crystals Length scales ≈ 1 Å → required wavelengths ≈ 1 Å 12,4 λ (Å) ≈ 12,4keV =ˆ 1Å • photons: E(keV) • electrons: • neutrons: • He atoms:
12,3
λ (Å) ≈ λ (Å) ≈ λ (Å) ≈
E ( eV ) 0,287 E ( eV ) 0,144 E ( eV )
100 eV =ˆ 1,23Å 10 meV =ˆ 2,87 Å 10 meV =ˆ 1,44Å
Example: Neutron diffraction from FeCo
disordered Introduction to solid state physics M. Wolf
ordered WS 2005/06 sheet 3.7
X-ray diffraction Laue method
Diffraction of collimated, broadband X-rays (k’≤ k0 ≤ k”) at single crystal sample: → analysis of crystal symmetry → orientation of single crystals Debeye-Scherrer method