Crystal Lab › Prototype structures › Orthorhombic
K3₃ (Tl₂AlF₅)
Orthorhombic · space group C2221 (No. 20) · Pearson oC32 · Strukturbericht K33
Symmetry elements and Wyckoff positions (interactive)
K3₃ (Tl₂AlF₅) in C2221
SettingUnit cell
- Lattice constants
- a = 8.240 Å, b = 10.060 Å, c = 7.460 Å; α = 90.00°, β = 90.00°, γ = 90.00°
- Cell volume
- 618.4 ų
- Atoms in the conventional cell
- 32 (Al 4, F 20, Tl 8)
- Formula units Z
- 4
- Pearson symbol
- oC32 — orthorhombic, base-centred lattice, 32 atoms per conventional cell
- Symmetry operations
- 8 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| Al1 | Al | 4a | 4 | 0.0000 | 0.0000 | 0.0000 |
| F3 | F | 4a | 4 | 0.7700 | 0.0000 | 0.0000 |
| F4 | F | 4a | 4 | 0.2200 | 0.0000 | 0.0000 |
| F2 | F | 4b | 4 | 0.0000 | 0.9670 | 0.2500 |
| F5 | F | 8c | 8 | 0.5000 | 0.3100 | 0.5400 |
| Tl6 | Tl | 8c | 8 | 0.7000 | 0.2100 | 0.2500 |
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 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
AB5C2_oC32_20_a_2abc_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oC32, then the space-group number 20, then the Wyckoff letters occupied by each element in turn (Al: 4a; F: 4a; F: 4a; F: 4b; F: 8c; Tl: 8c). Two structures with the same label are the same arrangement with different cell parameters or coordinates.
Note: K3₃.
Source
Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB5C2_oC32_20_a_2abc_c-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.
← α (low) Cristobalite · Space group C2221 (7 prototypes) · All prototypes