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Crystal Lab › Prototype structures › Trigonal

Low Temperature GaMo₄S₈

Trigonal · space group R3m (No. 160) · Pearson hR13

Symmetry elements and Wyckoff positions (interactive)

Low Temperature GaMo₄S₈ in R3m

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

Unit cell

Lattice constants
a = 6.906 Å, b = 6.906 Å, c = 16.713 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
690.2 ų
Atoms in the conventional cell
39 (Ga 3, Mo 12, Si 24)
Formula units Z
3
Pearson symbol
hR13 — hexagonal / trigonal, rhombohedral lattice, 13 atoms per conventional cell
Symmetry operations
18 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ga1Ga3a30.00000.00000.0000
Mo2Mo3a30.00000.00000.3990
Si4Si3a30.00000.00000.6360
Si5Si3a30.00000.00000.1350
Mo3Mo9b90.86070.13930.5353
Si6Si9b90.18470.81530.4573
Si7Si9b90.84870.15130.2893

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 39 atoms drawn above are these sites multiplied by all 18 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

AB4C8_hR13_160_a_ab_2a2b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR13, then the space-group number 160, then the Wyckoff letters occupied by each element in turn (Ga: 3a; Mo: 3a; Si: 3a; Si: 3a; Mo: 9b; Si: 9b; Si: 9b). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

GaV₄S₈ <!--beginning with an

Note: T < 45K.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB4C8_hR13_160_a_ab_2a2b-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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