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Selenic Acid (H₂SeO₃)

Orthorhombic · space group P212121 (No. 19) · Pearson oP28

Symmetry elements and Wyckoff positions (interactive)

Selenic Acid (H₂SeO₃) in P212121

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

Unit cell

Lattice constants
a = 8.333 Å, b = 8.129 Å, c = 4.591 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
311.0 ų
Atoms in the conventional cell
28 (H 8, O 16, Se 4)
Formula units Z
4
Pearson symbol
oP28 — orthorhombic, primitive lattice, 28 atoms per conventional cell
Symmetry operations
4 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
H1H4a40.45400.47900.5490
H2H4a40.22200.19500.0200
O3O4a40.51700.13100.7160
O4O4a40.28900.11100.3050
O5O4a40.23100.26600.8060
O6O4a40.41300.39000.4100
Se7Se4a40.36700.20900.5770

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 28 atoms drawn above are these sites multiplied by all 4 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

A2B4C_oP28_19_2a_4a_a-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oP28, then the space-group number 19, then the Wyckoff letters occupied by each element in turn (H: 4a; H: 4a; O: 4a; O: 4a; O: 4a; O: 4a; Se: 4a). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B4C_oP28_19_2a_4a_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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