X-ray scattering and Systematic Absences
a) Explain what is meant by "Lattice Constant" for a cubic crystal structure.
b) Explain why X-ray diffraction may be observed in first order from the (110) planes of a crystal with a body-centered cubic lattice, but not from the (110) planes of a crystal with a face-centered cubic lattice.
> Derive the general selection rules for which planes are observed in bcc and fcc lattices.
c) Show that these selection rules hold independent of what atoms are in the primitive unit cell, so long as the lattice is bcc or fcc, respectively.