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(NH₄)₃AlF₆ (J2₁)

Cubic · space group Fm-3m (No. 225) · Pearson cF200 · Strukturbericht J21

Symmetry elements and Wyckoff positions (interactive)

(NH₄)₃AlF₆ (J2₁) in Fm-3m

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

Unit cell

Lattice constants
a = 8.940 Å, b = 8.940 Å, c = 8.940 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
714.5 ų
Atoms in the conventional cell
200 (Al 4, N 12, F 120, H 64)
Formula units Z
4
Pearson symbol
cF200 — cubic, face-centred lattice, 200 atoms per conventional cell
Symmetry operations
192 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Al1Al4a40.00000.00000.0000
N6N4b40.50000.50000.5000
N7N8c80.25000.25000.2500
F2F24e240.19690.00000.0000
H4H32f320.19300.19300.1930
H5H32f320.55700.55700.5570
F3F96j960.00000.55360.6923

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 200 atoms drawn above are these sites multiplied by all 192 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

AB30C16D3_cF200_225_a_ej_2f_bc-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cF200, then the space-group number 225, then the Wyckoff letters occupied by each element in turn (Al: 4a; N: 4b; N: 8c; F: 24e; H: 32f; H: 32f; F: 96j). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

(NH₄)₃FeF₆, (NH₄)₃TiOF₅, (NH₄)₃Fe(NO₂)₆, K₃Ir(NO₂)₆, Cs₃Ir(NO₂)₆, Rb₃Ir(NO₂)₆, Tl₃Ir(NO₂)₆ <!--beginning with an

Note: J2₁.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB30C16D3_cF200_225_a_ej_2f_bc-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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