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La₃Al₁₁

Orthorhombic · space group Immm (No. 71) · Pearson oI28

Symmetry elements and Wyckoff positions (interactive)

La₃Al₁₁ in Immm

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

Unit cell

Lattice constants
a = 10.132 Å, b = 4.431 Å, c = 13.142 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
590.0 ų
Atoms in the conventional cell
28 (La 6, Al 22)
Formula units Z
2
Pearson symbol
oI28 — orthorhombic, body-centred lattice, 28 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
La5La2a20.00000.00000.0000
Al1Al2b20.00000.50000.5000
Al2Al4f40.28190.50000.0000
La6La4i40.00000.00000.3169
Al3Al8m80.36830.00000.3338
Al4Al8m80.27290.00000.1378

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 28 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

A11B3_oI28_71_bf2m_ai-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oI28, then the space-group number 71, then the Wyckoff letters occupied by each element in turn (La: 2a; Al: 2b; Al: 4f; La: 4i; Al: 8m; Al: 8m). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Ce₃Al₁₁, (La_{frac12}Nd_{frac12})₃Al₁₁, Sr₃In₁₁, Yb₃Zn₁₁, Yb₃(Al_{x}Zn_{11-x}, Ce₃(Al_{9.13}Ga_{1.78}Ni_{0.08}) <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A11B3_oI28_71_bf2m_ai-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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