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Mg₁₇Al₁₂

Cubic · space group I-43m (No. 217) · Pearson cI58

Symmetry elements and Wyckoff positions (interactive)

Mg₁₇Al₁₂ in I-43m

Setting
Loading the group…
x = 0.10, y = 0.17, z = 0.08

Unit 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

SiteElementWyckoffMultiplicityxyz
Mg2Mg2a20.00000.00000.0000
Mg3Mg8c80.32400.32400.3240
Al1Al24g240.09540.09540.2725
Mg4Mg24g240.35820.35820.0393

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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