Skip to content

Crystal Lab › Prototype structures › Trigonal

Ferroelectric LiNbO₃

Trigonal · space group R3c (No. 161) · Pearson hR10

Symmetry elements and Wyckoff positions (interactive)

Ferroelectric LiNbO₃ in R3c

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

Unit cell

Lattice constants
a = 5.254 Å, b = 5.254 Å, c = 13.876 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
331.7 ų
Atoms in the conventional cell
30 (Li 6, Nb 6, O 18)
Formula units Z
6
Pearson symbol
hR10 — hexagonal / trigonal, rhombohedral lattice, 10 atoms per conventional cell
Symmetry operations
18 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Li1Li6a60.00000.00000.2875
Nb2Nb6a60.00000.00000.0128
O3O18b180.05760.72070.0833

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 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

ABC3_hR10_161_a_a_b-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR10, then the space-group number 161, then the Wyckoff letters occupied by each element in turn (Li: 6a; Nb: 6a; O: 18b). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

BiFeO₃, CsPbF₃ <!--beginning with an

Note: Ferroelectric.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry ABC3_hR10_161_a_a_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.

← Stepanovite (NaMgFe(C₂O₄)₃cdot9H₂O)  ·  Space group R3c (5 prototypes)  ·  All prototypes