EM Course – Elastic Scattering

Professor Rodney Herring

Reciprocal Space

This chapter has been downloaded onto the Mech 580 Electron Microscopy website. Since the reciprocal lattice does not pertain to electron microscopy but is necessary to help interpret your diffraction, I want you to review it by yourself. I want you to take special attention to the Laue equations and their relation to Bragg’s law and its relation to higher order diffraction, Laue zone lines and acceleration voltage, and the excitation error, s.

Ewald Sphere

Diffracted beams are rods, which intersect the surface of the Ewald sphere. Even when tilted off exact Bragg diffraction, there is still some diffracted beam being created.

Ewald Sphere

Excitation Error – Deviation Parameter, S

Excitation Error – Deviation Parameter, S

Ewald Sphere, and E

Ewald Sphere