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Ca₇Ge

Cubic · space group Fm-3m (No. 225) · Pearson cF32

Symmetry elements and Wyckoff positions (interactive)

Ca₇Ge in Fm-3m

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

Unit cell

Lattice constants
a = 9.450 Å, b = 9.450 Å, c = 9.450 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
843.9 ų
Atoms in the conventional cell
32 (Ca 28, Ge 4)
Formula units Z
4
Pearson symbol
cF32 — cubic, face-centred lattice, 32 atoms per conventional cell
Symmetry operations
192 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ca1Ca4a40.00000.00000.0000
Ge3Ge4b40.50000.50000.5000
Ca2Ca24d240.00000.25000.2500

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 32 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

A7B_cF32_225_ad_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cF32, then the space-group number 225, then the Wyckoff letters occupied by each element in turn (Ca: 4a; Ge: 4b; Ca: 24d). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

CuPt₇, DyPd₇, LiPd₇, LiPt₇, SbPt₇, MoZn₇ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A7B_cF32_225_ad_b-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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