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Rb₂TiCu₂S₄

Tetragonal · space group P42/mcm (No. 132) · Pearson tP18

Symmetry elements and Wyckoff positions (interactive)

Rb₂TiCu₂S₄ in P42/mcm

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

Unit cell

Lattice constants
a = 5.605 Å, b = 5.605 Å, c = 13.154 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
413.2 ų
Atoms in the conventional cell
18 (Ti 2, Cu 4, Rb 4, S 8)
Formula units Z
2
Pearson symbol
tP18 — tetragonal, primitive lattice, 18 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ti4Ti2b20.00000.00000.2500
Cu1Cu4e40.00000.50000.2500
Rb2Rb4i40.73690.73690.0000
S3S8o80.76320.76320.3480

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 18 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

A2B2C4D_tP18_132_e_i_o_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tP18, then the space-group number 132, then the Wyckoff letters occupied by each element in turn (Ti: 2b; Cu: 4e; Rb: 4i; S: 8o). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Cs₂TiAg₂S₄, Cs₂TiCu₂Se₄ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B2C4D_tP18_132_e_i_o_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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