Crystal Lab › Prototype structures › Tetragonal
β-Bi₂O₃ (D5₁₂)
Tetragonal · space group P-4b2 (No. 117) · Pearson tP20 · Strukturbericht D512
Symmetry elements and Wyckoff positions (interactive)
β-Bi₂O₃ (D5₁₂) in P-4b2
SettingUnit cell
- Lattice constants
- a = 7.730 Å, b = 7.730 Å, c = 5.620 Å; α = 90.00°, β = 90.00°, γ = 90.00°
- Cell volume
- 335.8 ų
- Atoms in the conventional cell
- 20 (O 12, Bi 8)
- Formula units Z
- 4
- Pearson symbol
- tP20 — tetragonal, primitive lattice, 20 atoms per conventional cell
- Symmetry operations
- 8 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| O2 | O | 2a | 2 | 0.0000 | 0.0000 | 0.0000 |
| O3 | O | 2d | 2 | 0.0000 | 0.5000 | 0.5000 |
| O4 | O | 4g | 4 | 0.2300 | 0.7300 | 0.0000 |
| O5 | O | 4h | 4 | 0.2300 | 0.7300 | 0.5000 |
| Bi1 | Bi | 8i | 8 | 0.0200 | 0.2500 | 0.7500 |
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 20 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
A2B3_tP20_117_i_adgh-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tP20, then the space-group number 117, then the Wyckoff letters occupied by each element in turn (O: 2a; O: 2d; O: 4g; O: 4h; Bi: 8i). Two structures with the same label are the same arrangement with different cell parameters or coordinates.
Note: D5₁₂, \beta-Bi₂O₃.
Source
Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B3_tP20_117_i_adgh-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.