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Proustite (Ag₃AsS₃)

Trigonal · space group R3c (No. 161) · Pearson hR14 · mineral: proustite

Symmetry elements and Wyckoff positions (interactive)

Proustite (Ag₃AsS₃) in R3c

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

Unit cell

Lattice constants
a = 10.740 Å, b = 10.740 Å, c = 8.640 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
863.1 ų
Atoms in the conventional cell
42 (As 6, Ag 18, S 18)
Formula units Z
6
Pearson symbol
hR14 — hexagonal / trigonal, rhombohedral lattice, 14 atoms per conventional cell
Symmetry operations
18 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
As2As6a60.00000.00000.0000
Ag1Ag18b180.71870.08730.5683
S3S18b180.87500.78000.3850

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 42 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

A3BC3_hR14_161_b_a_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR14, then the space-group number 161, then the Wyckoff letters occupied by each element in turn (As: 6a; Ag: 18b; S: 18b). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Ag₃AsSe₃, Ag₃SbS₃ (pyrargyrite) <!--beginning with an

Note: Proustite.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A3BC3_hR14_161_b_a_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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