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Crystal Lab › Prototype structures › Hexagonal

PI₃

Hexagonal · space group P63 (No. 173) · Pearson hP8

Symmetry elements and Wyckoff positions (interactive)

PI₃ in P63

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

Unit 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

SiteElementWyckoffMultiplicityxyz
P2P2b20.33330.66670.0000
I1I6c60.03370.34750.1460

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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