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Na_{24-delta}Ge₁₃₆ Clathrate Ge₁₇Na₃

Cubic · space group Fd-3m (No. 227) · Pearson cF160

Symmetry elements and Wyckoff positions (interactive)

Na_{24-delta}Ge₁₃₆ Clathrate in Fd-3m

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

Unit cell

Lattice constants
a = 15.441 Å, b = 15.441 Å, c = 15.441 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
3681.4 ų
Atoms in the conventional cell
160 (Ge 136, Na 24)
Formula units Z
8
Pearson symbol
cF160 — cubic, face-centred lattice, 160 atoms per conventional cell
Symmetry operations
192 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ge1Ge8a80.12500.12500.1250
Na4Na8b80.37500.37500.3750
Na5Na16c160.00000.00000.0000
Ge2Ge32e320.21820.21820.2182
Ge3Ge96g960.06740.06740.3715

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 160 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

A17B3_cF160_227_aeg_bc-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cF160, then the space-group number 227, then the Wyckoff letters occupied by each element in turn (Ge: 8a; Na: 8b; Na: 16c; Ge: 32e; Ge: 96g). 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 A17B3_cF160_227_aeg_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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