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CeCu₂

Orthorhombic · space group Imma (No. 74) · Pearson oI12

Symmetry elements and Wyckoff positions (interactive)

CeCu₂ in Imma

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

Unit cell

Lattice constants
a = 4.430 Å, b = 7.050 Å, c = 7.450 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
232.7 ų
Atoms in the conventional cell
12 (Ce 4, Cu 8)
Formula units Z
4
Pearson symbol
oI12 — orthorhombic, body-centred lattice, 12 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ce1Ce4e40.00000.25000.5377
Cu2Cu8h80.00000.05100.1648

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 12 atoms drawn above are these sites multiplied by all 16 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

AB2_oI12_74_e_h-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oI12, then the space-group number 74, then the Wyckoff letters occupied by each element in turn (Ce: 4e; Cu: 8h). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

CaZn₂, CeAg₂, CeAu₂, CeCu₂, CeZn₂, DyCu₂, DyZn₂, ErCu₂, ErZn₂, EuAg₂, EuAu₂, EuCu₂, EuZn₂, GdCu₂, GdZn₂, HoCu₂, HoZn₂, LaAg₂, LaAu₂, LaZn₂, LuCu₂, LuZn₂, NdAg₂, NdCu₂, NdZn₂, PrAg₂, PrCu₂, PrZn₂, SmCu₂, SmZn₂, TbCu₂, ThZn₂, TmZn₂, YbAg₂, YbCu₂, YbZn₂ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB2_oI12_74_e_h-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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