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SrMn₇O₁₂

Trigonal · space group R-3 (No. 148) · Pearson hR20

Symmetry elements and Wyckoff positions (interactive)

SrMn₇O₁₂ in R-3

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

Unit cell

Lattice constants
a = 10.500 Å, b = 10.500 Å, c = 6.381 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
609.2 ų
Atoms in the conventional cell
60 (Mn 21, Sr 3, O 36)
Formula units Z
3
Pearson symbol
hR20 — hexagonal / trigonal, rhombohedral lattice, 20 atoms per conventional cell
Symmetry operations
18 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Mn1Mn3a30.00000.00000.0000
Sr6Sr3b30.00000.00000.5000
Mn2Mn9d90.50000.00000.5000
Mn3Mn9e90.50000.00000.0000
O4O18f180.03330.27530.5813
O5O18f180.17860.52050.8425

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 60 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

A7B12C_hR20_148_ade_2f_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR20, then the space-group number 148, then the Wyckoff letters occupied by each element in turn (Mn: 3a; Sr: 3b; Mn: 9d; Mn: 9e; O: 18f; O: 18f). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

CaMn₇O₁₂, CdMn₇O₁₂, PbMn₇O₁₂, PrMn₇O₁₂ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A7B12C_hR20_148_ade_2f_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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