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Al₆C₃N₂

Trigonal · space group R-3m (No. 166) · Pearson hR11

Symmetry elements and Wyckoff positions (interactive)

Al₆C₃N₂ in R-3m

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

Unit cell

Lattice constants
a = 3.248 Å, b = 3.248 Å, c = 40.030 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
365.7 ų
Atoms in the conventional cell
33 (C 9, Al 18, N 6)
Formula units Z
3
Pearson symbol
hR11 — hexagonal / trigonal, rhombohedral lattice, 11 atoms per conventional cell
Symmetry operations
36 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
C4C3a30.00000.00000.0000
Al1Al6c60.00000.00000.0857
Al2Al6c60.00000.00000.1921
Al3Al6c60.00000.00000.3091
C5C6c60.00000.00000.1355
N6N6c60.00000.00000.2595

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 33 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

A6B3C2_hR11_166_3c_ac_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR11, then the space-group number 166, then the Wyckoff letters occupied by each element in turn (C: 3a; Al: 6c; Al: 6c; Al: 6c; C: 6c; N: 6c). 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 A6B3C2_hR11_166_3c_ac_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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