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Herbertsmithite (Cu₃Zn(OH)₆Cl₂)

Trigonal · space group R-3m (No. 166) · Pearson hR18 · mineral: herbertsmithite

Symmetry elements and Wyckoff positions (interactive)

Herbertsmithite (Cu₃Zn(OH)₆Cl₂) in R-3m

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

Unit cell

Lattice constants
a = 6.834 Å, b = 6.834 Å, c = 14.075 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
569.3 ų
Atoms in the conventional cell
54 (Zn 3, Cl 6, Cu 9, H 18, O 18)
Formula units Z
3
Pearson symbol
hR18 — hexagonal / trigonal, rhombohedral lattice, 18 atoms per conventional cell
Symmetry operations
36 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Zn5Zn3a30.00000.00000.0000
Cl1Cl6c60.00000.00000.6943
Cu2Cu9d90.50000.00000.5000
H3H18h180.13800.86200.5862
O4O18h180.20560.79440.5612

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 54 atoms drawn above are these sites multiplied by all 36 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

A2B3C6D6E_hR18_166_c_d_h_h_a-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR18, then the space-group number 166, then the Wyckoff letters occupied by each element in turn (Zn: 3a; Cl: 6c; Cu: 9d; H: 18h; O: 18h). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Cu₃Ni(OH)₆Cl₂ (gillardite), Cu₃Mg_{x}(OH)₆Cl₂, Cu₃M(OH)₆Cl₂ (leverettite), Mg₃Mn_{x}(OH)₆Cl₂ <!--beginning with an

Note: Herbertsmithite.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B3C6D6E_hR18_166_c_d_h_h_a-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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