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Crystal Lab › Prototype structures › Orthorhombic

CaFe₃O₅

Orthorhombic · space group Cmcm (No. 63) · Pearson oC36

Symmetry elements and Wyckoff positions (interactive)

CaFe₃O₅ in Cmcm

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

Unit cell

Lattice constants
a = 3.021 Å, b = 10.009 Å, c = 12.643 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
382.3 ų
Atoms in the conventional cell
36 (Fe 12, Ca 4, O 20)
Formula units Z
4
Pearson symbol
oC36 — orthorhombic, base-centred lattice, 36 atoms per conventional cell
Symmetry operations
16 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Fe2Fe4a40.00000.00000.0000
Ca1Ca4c40.00000.52000.2500
O4O4c40.00000.19100.2500
Fe3Fe8f80.00000.26640.1112
O5O8f80.00000.64390.4484
O6O8f80.00000.90480.1350

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 36 atoms drawn above are these sites multiplied by all 16 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

AB3C5_oC36_63_c_af_c2f-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oC36, then the space-group number 63, then the Wyckoff letters occupied by each element in turn (Fe: 4a; Ca: 4c; O: 4c; Fe: 8f; O: 8f; O: 8f). 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 AB3C5_oC36_63_c_af_c2f-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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