Atomic01 - University of Cape Town
Atomic01 - University of Cape Town
Atomic01 - University of Cape Town
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
PHY322S Atomic Physics .<br />
Electron diffraction (cont.)<br />
Interpretation: similar to Bragg<br />
scattering <strong>of</strong> X-rays from crystals.<br />
Path difference: Constructive<br />
interference path difference a whole<br />
number <strong>of</strong> wavelengths<br />
a(cos θ r − cos θ i ) = nλ<br />
Note difference from usual Bragg<br />
Law geometry: scattering planes<br />
are oriented perpendicular to<br />
surface.<br />
Note θ i not necessarily equal to θ r .<br />
Electron scattering dominated by<br />
surface layers.<br />
29
Change language