Skip to content

Crystal Lab › Prototype structures › Tetragonal

Y-MgNiSn

Tetragonal · space group P42cm (No. 101) · Pearson tP32

Symmetry elements and Wyckoff positions (interactive)

Y-MgNiSn in P42cm

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

Unit cell

Lattice constants
a = 9.851 Å, b = 9.851 Å, c = 6.868 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
666.5 ų
Atoms in the conventional cell
32 (Mg 14, Ni 14, Sn 4)
Formula units Z
2
Pearson symbol
tP32 — tetragonal, primitive lattice, 32 atoms per conventional cell
Symmetry operations
8 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Mg1Mg2a20.00000.00000.0730
Ni4Ni2b20.50000.50000.1038
Mg2Mg4d40.22540.22540.7328
Ni5Ni4d40.30930.30930.0644
Sn7Sn4d40.17140.17140.3336
Mg3Mg8e80.23840.47560.3471
Ni6Ni8e80.03520.34490.0449

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 32 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

A7B7C2_tP32_101_ade_bde_d-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tP32, then the space-group number 101, then the Wyckoff letters occupied by each element in turn (Mg: 2a; Ni: 2b; Mg: 4d; Ni: 4d; Sn: 4d; Mg: 8e; Ni: 8e). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: Y-MgNiSn.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A7B7C2_tP32_101_ade_bde_d-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.

← [(CH₃)₄N][Cu₂(NCS)₃]  ·  Space group P42cm (2 prototypes)  ·  All prototypes