Crystal Lab › The 230 space groups › Hexagonal
No. 194 P 63/m m c
Hexagonal space group · 24 symmetry operations per cell · 12 Wyckoff positions
Symmetry elements and Wyckoff positions (interactive)
No. 194 P 63/m m c
SettingLoading the group…
x = 0.10, y = 0.17, z = 0.08
- Number
- 194
- Hermann–Mauguin symbol
- P 63/m m c
- Hall symbol
-P 6c 2c- Crystal system
- Hexagonal
- Operations per cell
- 24
- General position
- 24l (site symmetry 1)
Wyckoff positions (standard setting)
| Multiplicity | Letter | Site symmetry |
|---|---|---|
| 24 | l | 1 |
| 12 | k | .m. |
| 12 | j | m.. |
| 12 | i | .2. |
| 6 | h | mm2 |
| 6 | g | .2/m. |
| 4 | f | 3m. |
| 4 | e | 3m. |
| 2 | d | -6m2 |
| 2 | c | -6m2 |
| 2 | b | -6m2 |
| 2 | a | -3m. |
How to read it
- Each symmetry element drawn in the cell is worked out from the group’s operations: rotation and screw axes as lines (arrow = direction; dashed = screw), mirror and glide planes as sheets (dashed outline = glide), inversion centres as dots; rotoinversion axes are dotted. Colours: 2-fold red, 3-fold green, 4-fold blue, 6-fold purple.
- The multiplicity is how many equivalent points an atom on that site generates in the conventional cell; the general position has the highest multiplicity, equal to the number of operations.
- Site symmetry is the point group that leaves that position fixed; a special position (lower multiplicity) sits on a symmetry element — press + on a row to see its atoms land on the drawn elements.
Crystal Lab structures in this group
- Hexagonal close-packed (Mg) — Elemental
- Graphite (C) — Covalent layers
- Nickel arsenide (NiAs) — AB, 6:6 (hcp)
- Molybdenite (MoS₂) — Layered AB₂, 6:3
- Ice Ih (oxygen framework) (H₂O) — Hydrogen-bonded network