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BC8 (Si)

Cubic · space group Ia-3 (No. 206) · Pearson cI16

Symmetry elements and Wyckoff positions (interactive)

BC8 (Si) in Ia-3

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

Unit cell

Lattice constants
a = 4.120 Å, b = 4.120 Å, c = 4.120 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
69.9 ų
Atoms in the conventional cell
16 (Si 16)
Formula units Z
16
Pearson symbol
cI16 — cubic, body-centred lattice, 16 atoms per conventional cell
Symmetry operations
48 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Si1Si16c160.10010.10010.1001

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 16 atoms drawn above are these sites multiplied by all 48 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

A_cI16_206_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cI16, then the space-group number 206, then the Wyckoff letters occupied by each element in turn (Si: 16c). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: BC8 Si.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A_cI16_206_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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