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High Temperature K₂LiAlF₆ AlF₆K₂Li

Trigonal · space group R-3m (No. 166) · Pearson hR20

Symmetry elements and Wyckoff positions (interactive)

High Temperature K₂LiAlF₆ in R-3m

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

Unit cell

Lattice constants
a = 5.620 Å, b = 5.620 Å, c = 27.620 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
755.5 ų
Atoms in the conventional cell
60 (Al 6, K 12, Li 6, F 36)
Formula units Z
6
Pearson symbol
hR20 — hexagonal / trigonal, rhombohedral lattice, 20 atoms per conventional cell
Symmetry operations
36 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Al1Al3a30.00000.00000.0000
Al2Al3b30.00000.00000.5000
K5K6c60.00000.00000.1278
K6K6c60.00000.00000.2803
Li7Li6c60.00000.00000.4033
F3F18h180.48070.51930.1275
F4F18h180.51430.48570.2956

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 60 atoms drawn above are these sites multiplied by all 36 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

AB6C2D_hR20_166_ab_2h_2c_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR20, then the space-group number 166, then the Wyckoff letters occupied by each element in turn (Al: 3a; Al: 3b; K: 6c; K: 6c; Li: 6c; F: 18h; F: 18h). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Ba₂MnTeO₆, Cs₂NaCrF₆ <!--beginning with an

Note: HT.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB6C2D_hR20_166_ab_2h_2c_c-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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