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Mg₁₇Al₁₂
Cubic · space group I-43m (No. 217) · Pearson cI58
Symmetry elements and Wyckoff positions (interactive)
Mg₁₇Al₁₂ in I-43m
SettingUnit cell
- Lattice constants
- a = 10.543 Å, b = 10.543 Å, c = 10.543 Å; α = 90.00°, β = 90.00°, γ = 90.00°
- Cell volume
- 1171.9 ų
- Atoms in the conventional cell
- 58 (Mg 34, Al 24)
- Formula units Z
- 2
- Pearson symbol
- cI58 — cubic, body-centred lattice, 58 atoms per conventional cell
- Symmetry operations
- 48 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| Mg2 | Mg | 2a | 2 | 0.0000 | 0.0000 | 0.0000 |
| Mg3 | Mg | 8c | 8 | 0.3240 | 0.3240 | 0.3240 |
| Al1 | Al | 24g | 24 | 0.0954 | 0.0954 | 0.2725 |
| Mg4 | Mg | 24g | 24 | 0.3582 | 0.3582 | 0.0393 |
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 58 atoms drawn above are these sites multiplied by all 48 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
A12B17_cI58_217_g_acg-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cI58, then the space-group number 217, then the Wyckoff letters occupied by each element in turn (Mg: 2a; Mg: 8c; Al: 24g; Mg: 24g). 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 A12B17_cI58_217_g_acg-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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