Skip to content

Crystal Lab › Prototype structures › Cubic

Cd₈As₇Cl

Cubic · space group P23 (No. 195) · Pearson cP20

Symmetry elements and Wyckoff positions (interactive)

Cd₈As₇Cl in P23

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

Unit cell

Lattice constants
a = 7.266 Å, b = 7.266 Å, c = 7.266 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
383.6 ų
Atoms in the conventional cell
20 (As 7, Cl 1, Cd 12)
Formula units Z
1
Pearson symbol
cP20 — cubic, primitive lattice, 20 atoms per conventional cell
Symmetry operations
12 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
As1As1a10.00000.00000.0000
Cl2Cl1b10.50000.50000.5000
Cd3Cd4e40.21700.21700.2170
Cd4Cd4e40.71580.71580.7158
Cd5Cd4e40.76370.76370.7637
As6As6g60.33280.00000.5000

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 20 atoms drawn above are these sites multiplied by all 12 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

A7B12C_cP20_195_ag_3e_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol cP20, then the space-group number 195, then the Wyckoff letters occupied by each element in turn (As: 1a; Cl: 1b; Cd: 4e; Cd: 4e; Cd: 4e; As: 6g). 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 A7B12C_cP20_195_ag_3e_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.

← PrRu₄P₁₂  ·  Space group P23 (2 prototypes)  ·  All prototypes