Crystal Lab › Prototype structures › Hexagonal
PI₃
Hexagonal · space group P63 (No. 173) · Pearson hP8
Symmetry elements and Wyckoff positions (interactive)
PI₃ in P63
SettingUnit cell
- Lattice constants
- a = 7.133 Å, b = 7.133 Å, c = 7.414 Å; α = 90.00°, β = 90.00°, γ = 120.00°
- Cell volume
- 326.7 ų
- Atoms in the conventional cell
- 8 (P 2, I 6)
- Formula units Z
- 2
- Pearson symbol
- hP8 — hexagonal / trigonal, primitive lattice, 8 atoms per conventional cell
- Symmetry operations
- 6 per cell
Crystallographic sites
| Site | Element | Wyckoff | Multiplicity | x | y | z |
|---|---|---|---|---|---|---|
| P2 | P | 2b | 2 | 0.3333 | 0.6667 | 0.0000 |
| I1 | I | 6c | 6 | 0.0337 | 0.3475 | 0.1460 |
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 8 atoms drawn above are these sites multiplied by all 6 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
A3B_hP8_173_c_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP8, then the space-group number 173, then the Wyckoff letters occupied by each element in turn (P: 2b; I: 6c). Two structures with the same label are the same arrangement with different cell parameters or coordinates.
Other compounds with this structure
HCl₃ <!--beginning with an
Source
Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A3B_hP8_173_c_b-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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