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Base-Centered Monoclinic La₂CuO₄ CuLa₂O₄

Monoclinic · space group C1m1 (No. 8) · Pearson mC28

Symmetry elements and Wyckoff positions (interactive)

Base-Centered Monoclinic La₂CuO₄ in C1m1

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

Unit cell

Lattice constants
a = 13.143 Å, b = 5.357 Å, c = 5.406 Å; α = 90.00°, β = 90.00°, γ = 90.00°
Cell volume
380.6 ų
Atoms in the conventional cell
28 (Cu 4, La 8, O 16)
Formula units Z
4
Pearson symbol
mC28 — monoclinic, base-centred lattice, 28 atoms per conventional cell
Symmetry operations
4 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Cu1Cu2a20.00160.00000.0010
Cu2Cu2a20.49840.00000.4997
La3La2a20.63850.00000.9933
La4La2a20.36150.00000.0067
La5La2a20.13850.00000.5067
La6La2a20.86150.00000.4933
O10O2a20.31640.00000.5300
O7O2a20.81640.00000.0300
O8O2a20.18370.00000.9620
O9O2a20.68360.00000.5380
O11O4b40.00700.75000.2497
O12O4b40.49250.25000.7496

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 28 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

AB2C4_mC28_8_2a_4a_4a2b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol mC28, then the space-group number 8, then the Wyckoff letters occupied by each element in turn (Cu: 2a; Cu: 2a; La: 2a; La: 2a; La: 2a; La: 2a; O: 2a; O: 2a; O: 2a; O: 2a; O: 4b; O: 4b). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: BCM La₂CuO₄.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB2C4_mC28_8_2a_4a_4a2b-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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