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β-AlF₃

Orthorhombic · space group Cmcm (No. 63) · Pearson oC48

Symmetry elements and Wyckoff positions (interactive)

β-AlF₃ in Cmcm

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

Unit cell

Lattice constants
a = 6.930 Å, b = 12.002 Å, c = 7.134 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
593.4 ų
Atoms in the conventional cell
48 (Al 12, F 36)
Formula units Z
12
Pearson symbol
oC48 — orthorhombic, base-centred lattice, 48 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Al1Al4a40.00000.00000.0000
F3F4c40.00000.01770.2500
Al2Al8d80.25000.25000.0000
F4F8f80.00000.71250.5257
F5F8g80.72970.23520.2500
F6F16h160.81610.10540.9800

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 48 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

AB3_oC48_63_ad_cfgh-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oC48, then the space-group number 63, then the Wyckoff letters occupied by each element in turn (Al: 4a; F: 4c; Al: 8d; F: 8f; F: 8g; F: 16h). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

alpha'-AlH₃, β-GaF₃, β-InF₃ <!--beginning with an

Note: \beta-AlF₃.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB3_oC48_63_ad_cfgh-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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