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.
Read more about this topic: Brillouin Zone
Famous quotes containing the words critical and/or points:
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—Willard Van Orman Quine (b. 1908)