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Cu₄Pd

Tetragonal · space group P42/m (No. 84) · Pearson tP20

Symmetry elements and Wyckoff positions (interactive)

Cu₄Pd in P42/m

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

Unit cell

Lattice constants
a = 5.826 Å, b = 5.826 Å, c = 7.328 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
248.7 ų
Atoms in the conventional cell
20 (Cu 16, Pd 4)
Formula units Z
4
Pearson symbol
tP20 — tetragonal, primitive lattice, 20 atoms per conventional cell
Symmetry operations
8 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Cu1Cu2a20.00000.00000.0000
Cu2Cu2f20.50000.50000.2500
Cu3Cu4j40.20000.60000.0000
Pd5Pd4j40.40000.20000.0000
Cu4Cu8k80.10000.30000.2500

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 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

A4B_tP20_84_afjk_j-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tP20, then the space-group number 84, then the Wyckoff letters occupied by each element in turn (Cu: 2a; Cu: 2f; Cu: 4j; Pd: 4j; Cu: 8k). 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 A4B_tP20_84_afjk_j-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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