Crystal Lab › Prototype structures › Tetragonal
CeCo₄B₄
Tetragonal · space group P42/nmc (No. 137) · Pearson tP18
Symmetry elements and Wyckoff positions (interactive)
CeCo₄B₄ in P42/nmc
SettingUnit cell
- Lattice constants
- a = 5.059 Å, b = 5.059 Å, c = 7.063 Å; α = 90.00°, β = 90.00°, γ = 90.00°
- Cell volume
- 180.8 ų
- Atoms in the conventional cell
- 18 (Ce 2, B 8, Co 8)
- Formula units Z
- 2
- Pearson symbol
- tP18 — tetragonal, primitive lattice, 18 atoms per conventional cell
- Symmetry operations
- 16 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| Ce2 | Ce | 2a | 2 | 0.7500 | 0.2500 | 0.7500 |
| B1 | B | 8g | 8 | 0.2500 | 0.0800 | 0.6000 |
| Co3 | Co | 8g | 8 | 0.2500 | 0.5030 | 0.8840 |
The multiplicity and the Wyckoff letter say how many copies of the site the group makes in one cell and on which kind of symmetry element the site sits; the 18 atoms drawn above are these sites multiplied by all 16 operations. Press Wyckoff under Colour to see the sites, and tick a symmetry element on the left to see which atoms lie on it.
How to read the label
A4BC4_tP18_137_g_a_g-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tP18, then the space-group number 137, then the Wyckoff letters occupied by each element in turn (Ce: 2a; B: 8g; Co: 8g). Two structures with the same label are the same arrangement with different cell parameters or coordinates.
Source
Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A4BC4_tP18_137_g_a_g-001 (M. J. Mehl et al., Comput. Mater. Sci. 136, S1 (2017); D. Hicks et al., ibid. 161, S1 (2019) and 199, 110450 (2021); S. Eckert et al., ibid. 240, 112988 (2024)). Symmetry elements, Wyckoff assignment and the diagram are computed on this page from the group operations.
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