Brillouin Zone - Critical Points

Critical Points

Several points of high symmetry are of special interest – these are called critical points.

Symbol Description
Γ Center of the Brillouin zone
Simple cube
M Center of an edge
R Corner point
X Center of a face
Face-centered cubic
K Middle of an edge joining two hexagonal faces
L Center of a hexagonal face
U Middle of an edge joining a hexagonal and a square face
W Corner point
X Center of a square face
Body-centered cubic
H Corner point joining four edges
N Center of a face
P Corner point joining three edges
Hexagonal
A Center of a hexagonal face
H Corner point
K Middle of an edge joining two rectangular faces
L Middle of an edge joining a hexagonal and a rectangular face
M Center of a rectangular face

Other lattices have different types of high-symmetry points. They can be found in the illustrations below.

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