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Cs₃As₂Cl₉ (K7₃)

Trigonal · space group P321 (No. 150) · Pearson hP14 · Strukturbericht K73

Symmetry elements and Wyckoff positions (interactive)

Cs₃As₂Cl₉ (K7₃) in P321

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

Unit cell

Lattice constants
a = 7.370 Å, b = 7.370 Å, c = 8.910 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
419.1 ų
Atoms in the conventional cell
14 (Cs 3, As 2, Cl 9)
Formula units Z
1
Pearson symbol
hP14 — hexagonal / trigonal, primitive lattice, 14 atoms per conventional cell
Symmetry operations
6 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Cs4Cs1a10.00001.00000.0000
As1As2d20.33330.66670.8050
Cs5Cs2d20.33330.66670.3200
Cl2Cl3e30.48001.00000.0000
Cl3Cl6g60.36500.20000.3250

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 14 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

A2B9C3_hP14_150_d_eg_ad-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP14, then the space-group number 150, then the Wyckoff letters occupied by each element in turn (Cs: 1a; As: 2d; Cs: 2d; Cl: 3e; Cl: 6g). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: K7₃.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B9C3_hP14_150_d_eg_ad-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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