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Predicted Li₂MgH₁₆ 300 GPa H₁₆Li₂Mg

Trigonal · space group P-3m1 (No. 164) · Pearson hP19

Symmetry elements and Wyckoff positions (interactive)

Predicted Li₂MgH₁₆ 300 GPa in P-3m1

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

Unit cell

Lattice constants
a = 2.796 Å, b = 2.796 Å, c = 5.313 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
36.0 ų
Atoms in the conventional cell
19 (Mg 1, H 16, Li 2)
Formula units Z
1
Pearson symbol
hP19 — hexagonal / trigonal, primitive lattice, 19 atoms per conventional cell
Symmetry operations
12 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Mg6Mg1a10.00000.00000.0000
H1H2d20.33330.66670.0745
H2H2d20.33330.66670.8914
Li5Li2d20.33330.66670.3363
H3H6i60.17160.82840.5797
H4H6i60.16440.83560.7365

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 19 atoms drawn above are these sites multiplied by all 12 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

A16B2C_hP19_164_2d2i_d_a-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP19, then the space-group number 164, then the Wyckoff letters occupied by each element in turn (Mg: 1a; H: 2d; H: 2d; Li: 2d; H: 6i; H: 6i). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Note: Predicted, 300 GPa.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry A16B2C_hP19_164_2d2i_d_a-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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