Skip to content

Crystal Lab › Prototype structures › Tetragonal

NaS₂

Tetragonal · space group I-42d (No. 122) · Pearson tI48

Symmetry elements and Wyckoff positions (interactive)

NaS₂ in I-42d

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

Unit cell

Lattice constants
a = 9.597 Å, b = 9.597 Å, c = 11.789 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
1085.6 ų
Atoms in the conventional cell
48 (Na 16, S 32)
Formula units Z
16
Pearson symbol
tI48 — tetragonal, body-centred lattice, 48 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Na1Na8c80.00000.00000.1695
Na2Na8d80.27650.25000.1250
S3S16e160.03370.24950.2964
S4S16e160.64690.61600.8996

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 48 atoms drawn above are these sites multiplied by all 16 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

AB2_tI48_122_cd_2e-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tI48, then the space-group number 122, then the Wyckoff letters occupied by each element in turn (Na: 8c; Na: 8d; S: 16e; S: 16e). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB2_tI48_122_cd_2e-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.

← NH₄H₂PO₄  ·  Space group I-42d (7 prototypes)  ·  All prototypes  ·  Chalcopyrite (CuFeS₂, E1₁) →