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β'-AuCd (B19)

Orthorhombic · space group Pmma (No. 51) · Pearson oP4 · Strukturbericht B19

Symmetry elements and Wyckoff positions (interactive)

β'-AuCd (B19) in Pmma

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

Unit cell

Lattice constants
a = 4.755 Å, b = 3.148 Å, c = 4.855 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
72.7 ų
Atoms in the conventional cell
4 (Au 2, Cd 2)
Formula units Z
2
Pearson symbol
oP4 — orthorhombic, primitive lattice, 4 atoms per conventional cell
Symmetry operations
8 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Au1Au2e20.25000.00000.8125
Cd2Cd2f20.25000.50000.3125

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 4 atoms drawn above are these sites multiplied by all 8 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

AB_oP4_51_e_f-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oP4, then the space-group number 51, then the Wyckoff letters occupied by each element in turn (Au: 2e; Cd: 2f). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

AuTi (H.T.), CdMg, IrMo, IrW, MoPt (H.T.), MoRh, NbPt, NbRh, TiPb, TiPd, TiPt, VPt (L.T.) <!--beginning with an

Note: B19, \beta'-AuCd.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB_oP4_51_e_f-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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