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Crystal Lab › Prototype structures › Monoclinic

α-Bi₂O₃

Monoclinic · space group P121/c1 (No. 14) · Pearson mP20

Symmetry elements and Wyckoff positions (interactive)

α-Bi₂O₃ in P121/c1

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

Unit cell

Lattice constants
a = 5.850 Å, b = 8.165 Å, c = 7.510 Å; α = 90.00°, β = 112.98°, γ = 90.00°
Cell volume
330.2 ų
Atoms in the conventional cell
20 (Bi 8, O 12)
Formula units Z
4
Pearson symbol
mP20 — monoclinic, primitive lattice, 20 atoms per conventional cell
Symmetry operations
4 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Bi1Bi4e40.52420.18430.3615
Bi2Bi4e40.04040.04250.7767
O3O4e40.77830.30370.7080
O4O4e40.23370.04670.1266
O5O4e40.26580.02940.5115

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 20 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

A2B3_mP20_14_2e_3e-003: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol mP20, then the space-group number 14, then the Wyckoff letters occupied by each element in turn (Bi: 4e; Bi: 4e; O: 4e; O: 4e; O: 4e). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: α-Bi₂O₃.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A2B3_mP20_14_2e_3e-003 (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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