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K₄Cu₈Ge₃S₁₂

Cubic · space group Fm-3c (No. 226) · Pearson cF232

Symmetry elements and Wyckoff positions (interactive)

K₄Cu₈Ge₃S₁₂ in Fm-3c

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

Unit cell

Lattice constants
a = 17.728 Å, b = 17.728 Å, c = 17.728 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
5571.6 ų
Atoms in the conventional cell
232 (Ge 24, K 48, Cu 64, S 96)
Formula units Z
8
Pearson symbol
cF232 — cubic, face-centred lattice, 232 atoms per conventional cell
Symmetry operations
192 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ge2Ge24c240.25000.00000.0000
K3K48f480.42250.25000.2500
Cu1Cu64g640.58670.58670.5867
S4S96i960.00000.17830.6031

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 232 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

A8B3C6D12_cF232_226_g_c_f_i-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cF232, then the space-group number 226, then the Wyckoff letters occupied by each element in turn (Ge: 24c; K: 48f; Cu: 64g; S: 96i). 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 A8B3C6D12_cF232_226_g_c_f_i-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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