Crystal Lab › Prototype structures › Orthorhombic
La₃Al₁₁
Orthorhombic · space group Immm (No. 71) · Pearson oI28
Symmetry elements and Wyckoff positions (interactive)
La₃Al₁₁ in Immm
SettingUnit 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
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| La5 | La | 2a | 2 | 0.0000 | 0.0000 | 0.0000 |
| Al1 | Al | 2b | 2 | 0.0000 | 0.5000 | 0.5000 |
| Al2 | Al | 4f | 4 | 0.2819 | 0.5000 | 0.0000 |
| La6 | La | 4i | 4 | 0.0000 | 0.0000 | 0.3169 |
| Al3 | Al | 8m | 8 | 0.3683 | 0.0000 | 0.3338 |
| Al4 | Al | 8m | 8 | 0.2729 | 0.0000 | 0.1378 |
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.
· Space group Immm (13 prototypes) · All prototypes · Orthorhombic Fullerene (Cs₃C₆₀) →