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Nb₂Be₁₇

Trigonal · space group R-3m (No. 166) · Pearson hR19

Symmetry elements and Wyckoff positions (interactive)

Nb₂Be₁₇ in R-3m

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

Unit cell

Lattice constants
a = 7.355 Å, b = 7.355 Å, c = 10.762 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
504.2 ų
Atoms in the conventional cell
57 (Be 51, Nb 6)
Formula units Z
3
Pearson symbol
hR19 — hexagonal / trigonal, rhombohedral lattice, 19 atoms per conventional cell
Symmetry operations
36 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Be1Be6c60.00000.00000.3970
Nb5Nb6c60.00000.00000.1599
Be2Be9e90.50000.00000.0000
Be3Be18g180.70300.00000.5000
Be4Be18h180.83070.16930.3273

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 57 atoms drawn above are these sites multiplied by all 36 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

A17B2_hR19_166_cegh_c-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hR19, then the space-group number 166, then the Wyckoff letters occupied by each element in turn (Be: 6c; Nb: 6c; Be: 9e; Be: 18g; Be: 18h). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

α-Be₁₇Hf₂, Be₁₇Ta₂, α-Be₁₇Ti₂, Be₁₇Zr₂ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A17B2_hR19_166_cegh_c-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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