Skip to content

Crystal Lab › Prototype structures › Hexagonal

LaTa₇O₁₉

Hexagonal · space group P-6c2 (No. 188) · Pearson hP54

Symmetry elements and Wyckoff positions (interactive)

LaTa₇O₁₉ in P-6c2

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

Unit cell

Lattice constants
a = 6.230 Å, b = 6.230 Å, c = 19.990 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
671.9 ų
Atoms in the conventional cell
54 (La 2, Ta 14, O 38)
Formula units Z
2
Pearson symbol
hP54 — hexagonal / trigonal, primitive lattice, 54 atoms per conventional cell
Symmetry operations
12 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
La1La2a20.00000.00000.0000
Ta2Ta2c20.33330.66670.0000
O3O4g40.00000.00000.1270
O4O4h40.33330.66670.1640
O5O6k60.70770.74430.2500
O6O12l120.65670.08330.1560
O7O12l120.61070.70030.0610
Ta8Ta12l120.66470.69230.1563

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 54 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

AB19C7_hP54_188_a_ghk2l_cl-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP54, then the space-group number 188, then the Wyckoff letters occupied by each element in turn (La: 2a; Ta: 2c; O: 4g; O: 4h; O: 6k; O: 12l; O: 12l; Ta: 12l). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

BiTa₇O₁₉, DyTa₇O₁₉, GdTa₇O₁₉, HoTa₇O₁₉, NdTa₇O₁₉, PrTa₇O₁₉, SmTa₇O₁₉ <!--beginning with an

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB19C7_hP54_188_a_ghk2l_cl-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.

← LiScI₃  ·  Space group P-6c2 (4 prototypes)  ·  All prototypes  ·  BaSi₄O₉ (S3₂) →