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Cr-233 Quasi-One-Dimensional Superconductor (K₂Cr₃As₃)

Hexagonal · space group P-6m2 (No. 187) · Pearson hP16

Symmetry elements and Wyckoff positions (interactive)

Cr-233 Quasi-One-Dimensional Superconductor (K₂Cr₃As₃) in P-6m2

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

Unit cell

Lattice constants
a = 9.983 Å, b = 9.983 Å, c = 4.230 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
365.1 ų
Atoms in the conventional cell
16 (K 4, As 6, Cr 6)
Formula units Z
2
Pearson symbol
hP16 — hexagonal / trigonal, primitive lattice, 16 atoms per conventional cell
Symmetry operations
12 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
K5K1a10.00000.00000.0000
As1As3j30.50060.49940.0000
Cr3Cr3j30.75650.24350.0000
As2As3k30.83430.16570.5000
Cr4Cr3k30.57940.42060.5000
K6K3k30.20540.79460.5000

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 16 atoms drawn above are these sites multiplied by all 12 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

A3B3C2_hP16_187_jk_jk_ak-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP16, then the space-group number 187, then the Wyckoff letters occupied by each element in turn (K: 1a; As: 3j; Cr: 3j; As: 3k; Cr: 3k; K: 3k). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Cs₂Cr₃As₃, K₂Mo₃As₃, Rb₂Cr₃As₃, Rb₂Mo₃As₃ <!--beginning with an

Note: Quasi-1D Superconductor.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A3B3C2_hP16_187_jk_jk_ak-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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