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U₂Cr₃Si

Hexagonal · space group P63/mmc (No. 194) · Pearson hP12

Symmetry elements and Wyckoff positions (interactive)

U₂Cr₃Si in P63/mmc

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

Unit cell

Lattice constants
a = 5.125 Å, b = 5.125 Å, c = 8.265 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
188.0 ų
Atoms in the conventional cell
12 (Si 2, U 4, Cr 6)
Formula units Z
2
Pearson symbol
hP12 — hexagonal / trigonal, primitive lattice, 12 atoms per conventional cell
Symmetry operations
24 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Si1Si2a20.00000.00000.0000
U2U4f40.33330.66670.0625
Cr3Cr6h60.83330.66670.2500

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 12 atoms drawn above are these sites multiplied by all 24 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

A3BC2_hP12_194_h_a_f-002: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP12, then the space-group number 194, then the Wyckoff letters occupied by each element in turn (Si: 2a; U: 4f; Cr: 6h). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Dy₂Al₃Co, Co₂Nb₃Si, Er₂Al₃Co, Eu₂Ga₃Ir, Lu₂Al₃Co, Mg₂Cu₃Si, Mg₂Ir₃Si, Mn₂Co₃Ge, Mo₂Co₃Si, Nb₂Ni₃Si, Pd₂Ga₃U, Ru₂Al₃Sc, Sc₂Fe₃Si, Ta₂Cr₃Cu, Ta₂Ni₃Si, Ti₂Ni₃Si, U₂Al₃Cu, U₂Mn₃Ge, W₂Co₃Si, Zr₂Fe₃Ga, Zr₂Fe₃Ge, Zr₂V₃Ru <!--beginning with an

Note: Ternary Hexagonal Laves.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A3BC2_hP12_194_h_a_f-002 (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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