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Orthorhombic La₃Ni₂O₇

Orthorhombic · space group Fmmm (No. 69) · Pearson oF48

Symmetry elements and Wyckoff positions (interactive)

Orthorhombic La₃Ni₂O₇ in Fmmm

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

Unit cell

Lattice constants
a = 20.516 Å, b = 5.436 Å, c = 5.393 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
601.5 ų
Atoms in the conventional cell
48 (La 12, O 28, Ni 8)
Formula units Z
4
Pearson symbol
oF48 — orthorhombic, face-centred lattice, 48 atoms per conventional cell
Symmetry operations
32 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
La1La4a40.00000.00000.0000
O4O4b40.00000.00000.5000
La2La8g80.81910.00000.0000
Ni3Ni8g80.59750.00000.0000
O5O8g80.69900.00000.0000
O6O16l160.90050.25000.2500

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 48 atoms drawn above are these sites multiplied by all 32 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

A3B2C7_oF48_69_ag_g_bgl-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol oF48, then the space-group number 69, then the Wyckoff letters occupied by each element in turn (La: 4a; O: 4b; La: 8g; Ni: 8g; O: 8g; O: 16l). 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 A3B2C7_oF48_69_ag_g_bgl-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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