1What is the reciprocal lattice?
The lattice formed by wavevectors that satisfy Bragg scattering conditions.
2What is the defining relation between real and reciprocal lattice vectors?
aᵢ·bⱼ = 2πδᵢⱼ.
3What is the physical meaning of the reciprocal lattice?
It represents allowed momentum transfers in diffraction.
4What is a Wigner–Seitz cell?
The region closer to a given lattice point than any other.
5What is the first Brillouin zone?
The Wigner–Seitz cell of the reciprocal lattice.
6What is the reciprocal lattice of a square lattice?
A square lattice.
7Where are Brillouin zone boundaries located?
Halfway between reciprocal lattice points.
8Why are Brillouin zone boundaries important?
They correspond to Bragg reflection and band gap formation.