Skip to content

Crystal Lab › Prototype structures › Hexagonal

BaSi₄O₉ (S3₂)

Hexagonal · space group P-6c2 (No. 188) · Pearson hP28 · Strukturbericht S32

Symmetry elements and Wyckoff positions (interactive)

BaSi₄O₉ (S3₂) in P-6c2

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

Unit cell

Lattice constants
a = 6.495 Å, b = 6.495 Å, c = 9.347 Å; α = 90.00°, β = 90.00°, γ = 120.00°
Cell volume
341.5 ų
Atoms in the conventional cell
28 (Ba 2, Si 8, O 18)
Formula units Z
2
Pearson symbol
hP28 — hexagonal / trigonal, primitive lattice, 28 atoms per conventional cell
Symmetry operations
12 per cell

Crystallographic sites

SiteElementWyckoffMultiplicityxyz
Ba1Ba2a20.00000.00000.0000
Si4Si2c20.33330.66670.0000
O2O6k60.40440.14970.2500
Si5Si6k60.45360.42100.2500
O3O12l120.56260.66790.6032

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 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

AB9C4_hP28_188_a_kl_ck-001: the stoichiometry comes first (A, B, C… are the elements in alphabetical order of their site labels), then the Pearson symbol hP28, then the space-group number 188, then the Wyckoff letters occupied by each element in turn (Ba: 2a; Si: 2c; O: 6k; Si: 6k; O: 12l). Two structures with the same label are the same arrangement with different cell parameters or coordinates.

Other compounds with this structure

Ba(Si_{x}Ti_{1-x})Si₃O₉ (pabstite), BaSnGe₃O₉, BaTiSi₃O₉ (benitoite), BaZrSi₃O₉ (bazrite), CaKP₃O₉, MgKP₃O₉, TaKGe₃O₉, TaRbGe₃O₉, TaTlGe₃O₉ <!--beginning with an

Note: S3₂.

Source

Coordinates and cell from the AFLOW Encyclopedia of Crystallographic Prototypes, entry AB9C4_hP28_188_a_kl_ck-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.

← LaTa₇O₁₉  ·  Space group P-6c2 (4 prototypes)  ·  All prototypes