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Crystal Lab › Prototype structures › Tetragonal

Nd₄Ni₃O₈

Tetragonal · space group I4/mmm (No. 139) · Pearson tI30

Symmetry elements and Wyckoff positions (interactive)

Nd₄Ni₃O₈ in I4/mmm

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

Unit cell

Lattice constants
a = 3.915 Å, b = 3.915 Å, c = 25.295 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
387.6 ų
Atoms in the conventional cell
30 (Ni 6, O 16, Nd 8)
Formula units Z
2
Pearson symbol
tI30 — tetragonal, body-centred lattice, 30 atoms per conventional cell
Symmetry operations
32 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ni3Ni2a20.00000.00000.0000
O5O4c40.00000.50000.0000
O6O4d40.00000.50000.2500
Nd1Nd4e40.00000.00000.4343
Nd2Nd4e40.00000.00000.2982
Ni4Ni4e40.00000.00000.1244
O7O8g80.00000.50000.1262

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 30 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

A4B3C8_tI30_139_2e_ae_cdg-002: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol tI30, then the space-group number 139, then the Wyckoff letters occupied by each element in turn (Ni: 2a; O: 4c; O: 4d; Nd: 4e; Nd: 4e; Ni: 4e; O: 8g). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

La₄Ni₃O₈, Pr₄Ni₃O₈ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A4B3C8_tI30_139_2e_ae_cdg-002 (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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