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Eriochalcite (CuCl₂cdot2H₂O, C45)

Orthorhombic · space group Pmna (No. 53) · Pearson oP18 · Strukturbericht C45 · mineral: eriochalcite

Symmetry elements and Wyckoff positions (interactive)

Eriochalcite (CuCl₂cdot2H₂O, C45) in Pmna

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

Unit cell

Lattice constants
a = 8.089 Å, b = 3.746 Å, c = 7.414 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
224.6 ų
Atoms in the conventional cell
18 (Cu 2, O 4, Cl 4, H 8)
Formula units Z
2
Pearson symbol
oP18 — orthorhombic, primitive lattice, 18 atoms per conventional cell
Symmetry operations
8 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Cu2Cu2a20.00000.00000.0000
O4O4e40.24020.00000.0000
Cl1Cl4h40.00000.37980.2400
H3H8i80.27500.06400.0990

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 8 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

A2BC4D2_oP18_53_h_a_i_e-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oP18, then the space-group number 53, then the Wyckoff letters occupied by each element in turn (Cu: 2a; O: 4e; Cl: 4h; H: 8i). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: C45, Eriochalcite.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2BC4D2_oP18_53_h_a_i_e-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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