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Crystal Lab › Prototype structures › Trigonal

La₄Ge₃S₁₂

Trigonal · space group R3c (No. 161) · Pearson hR38

Symmetry elements and Wyckoff positions (interactive)

La₄Ge₃S₁₂ in R3c

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

Unit cell

Lattice constants
a = 19.400 Å, b = 19.400 Å, c = 8.100 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
2640.1 ų
Atoms in the conventional cell
114 (La 24, Ge 18, S 72)
Formula units Z
6
Pearson symbol
hR38 — hexagonal / trigonal, rhombohedral lattice, 38 atoms per conventional cell
Symmetry operations
18 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
La2La6a60.00000.00000.0000
Ge1Ge18b180.20000.18750.1523
La3La18b180.00300.23070.2028
S4S18b180.15490.37890.1618
S5S18b180.12460.06430.2511
S6S18b180.11450.20050.9974
S7S18b180.39600.05930.1817

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 114 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

A3B4C12_hR38_161_b_ab_4b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR38, then the space-group number 161, then the Wyckoff letters occupied by each element in turn (La: 6a; Ge: 18b; La: 18b; S: 18b; S: 18b; S: 18b; S: 18b). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Ce₄Ge₃S₁₂, Ce₄Si₃S₁₂, Fe₄C₃O₁₂, Gd₄Ge₃S₁₂, Gd₄Si₃S₁₂, Nd₄Ge₃S₁₂, Nd₄Si₃S₁₂, Pr₄Ge₃S₁₂, Pr₄Si₃S₁₂, Sm₄Ge₃S₁₂, Sm₄Si₃S₁₂ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A3B4C12_hR38_161_b_ab_4b-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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